Polymerization processes and polymers made therefrom

ABSTRACT

The present disclosure provides processes for polymerizing olefin(s). Methods can include contacting a first composition and a second composition in a line to form a third composition. The first composition can include a contact product of a first catalyst, a second catalyst, a support, a first activator, a mineral oil. The second composition can include a contact product of an activator, a diluent, and the first catalyst or the second catalyst. Methods can include introducing the third composition from the line into a gas-phase fluidized bed reactor, introducing a condensing agent to the line and/or the reactor, exposing the third composition to polymerization conditions, and/or obtaining a polyolefin. Polyethylene compositions including at least 65 wt % ethylene derived units, based upon the total weight of the polyethylene composition, are provided.

CROSS-REFERENCE OF RELATED APPLICATIONS

This Continuation-in-Part Application claims priority to and the benefitof U.S. Ser. No. 16/204,993 filed Nov. 29, 2018, U.S. Ser. No.16/152,470 filed Oct. 5, 2018, U.S. Ser. No. 16/152,458 filed Oct. 5,2018, U.S. Ser. No. 16/117,008 filed Aug. 30, 2018, and U.S. Ser. No.16/117,023 filed Aug. 30, 2018, the disclosures of which areincorporated herein by reference in their entireties. This applicationclaims priority to and the benefit of U.S. Provisional Applications Nos.62/754,217 filed Nov. 1, 2018, 62/754,224 filed Nov. 1, 2018, 62/754,231filed Nov. 1, 2018, 62/754,237 filed Nov. 1, 2018, 62/754,241 filed Nov.1, 2018, and 62/754,248 filed Nov. 1, 2018, the disclosures of which areincorporated herein by reference in its entirety.

FIELD OF THE INVENTION

The present disclosure relates to polymerization processes for producingpolyethylene and ethylene copolymers comprising polymerizing ethylene byusing mixed catalyst systems with properties tunable in polymerizationreactors and polymers resulting therefrom.

BACKGROUND OF THE INVENTION

Olefin polymerization catalysts are of great use in industry to producepolyolefin polymers and these polymers have revolutionized virtuallyevery aspect of the modern world. Hence, there is strong interest infinding new catalyst systems to use in polymerization processes thatincrease the commercial usefulness of the catalyst systems and allow theproduction of polyolefin polymers having improved properties or a newcombination of properties.

In particular, much effort has been placed in understanding how thecomonomer is distributed along the polymer carbon chain or simplypolymer chain of a polyolefin polymer. For example, the compositiondistribution of an ethylene alpha-olefin copolymer refers to thedistribution of comonomer (short chain branches) among the moleculesthat comprise the polyethylene polymer. When the amount of short chainbranches varies among the polymer carbon chain, the polymer or resin issaid to have a Broad Composition Distribution (BCD). When the amount ofcomonomer per about 1000 carbons is similar among the polyethylenemolecules of different polymer chain lengths or molecular weights, thecomposition distribution is said to be “narrow” or have a NarrowComposition Distribution (NCD).

The composition distribution is known to influence the properties ofcopolymers, for example, extractables content, environmental stresscrack resistance, heat sealing, dart drop impact resistance, and tearresistance or strength. The composition distribution of a polyolefin maybe readily measured by methods known in the art, for example,Temperature Raising Elution Fractionation (TREF) or CrystallizationAnalysis Fractionation (CRYSTAF). See, for example, U.S. Pat. No.8,378,043, Col. 3 and Col. 4.

Ethylene alpha-olefin copolymers may be produced in a low pressurereactor, utilizing, for example, solution, slurry, and/or gas phasepolymerization processes. Polymerization takes place in the presence ofactivated catalyst systems such as those employing a Ziegler-Nattacatalyst, a chromium based catalyst, a vanadium catalyst, a metallocenecatalyst, a mixed catalyst (i.e., two or more different catalystsco-supported on the same carrier such as a bimodal catalyst), otheradvanced catalysts, or combinations thereof. In general, these catalystswhen used in a catalyst system all produce a variety of polymer chainsin a polyolefin polymer composition that vary in molecular weight andcomonomer incorporation. In some cases, this variation becomes a“signature” to the catalyst itself.

For example, it is generally known in the art that a polyolefin'scomposition distribution is largely dictated by the type of catalystused. For example, Broad Composition Distribution or BCD refers topolymers in which the length of the molecules would be substantially thesame but the amount of the comonomer would vary along the length, forexample, for an ethylene-hexene copolymer, hexene distribution variesfrom low to high while the molecular weight is roughly the same or thePolydispersity Index (PDI) is narrow.

Polymers made with Zeigler Natta catalysts are considered to be“conventional” in which the composition distribution is broad but thehigh molecular weight fractions are higher density (i.e., lesscomonomer) than the lower molecular weight fraction (high comonomer).

In contrast, metallocene catalysts typically produce a polyolefinpolymer composition with an NCD. A metallocene catalyst is generally ametal complex of a transitional metal, typically, a Group 4 metal, andone or more cyclopentadienyl (Cp) ligands or rings. As stated above, NCDgenerally refers to the comonomer being evenly distributed or not varymuch along the polymer chain. An illustration is provided as FIG. 1A.

More recently, a third distribution has been described for a polyolefinpolymer composition having a Broad Orthogonal Composition Distribution(BOCD) in which the comonomer is incorporated predominantly in the highmolecular weight chains. A substituted hafnocene catalyst has been notedto produce this type of distribution. See, for example, U.S. Pat. Nos.6,242,545, 6,248,845, 6,528,597, 6,936,675, 6,956,088, 7,172,816,7,179,876, 7,381,783, 8,247,065, 8,378,043, 8,476,392; U.S. PatentApplication Publication No. 2015/0291748; and Ser. No. 62/461,104, filedFeb. 20, 2017, entitled Supported Catalyst Systems and Processes for UseThereof. An illustration is provided as FIG. 1b . This distribution hasbeen noted for its improved physical properties, for example, ease infabrication of end-use articles as well as stiffness and toughness inmultiple applications such as films that can be measured by dart dropimpact resistance and tear resistance or strength.

As taught by U.S. Pat. No. 8,378,043, BOCD refers to incorporating thecomonomer predominantly in the high molecular weight chains. Thedistribution of the short chain branches can be measured, for example,using Temperature Raising Elution Fractionation (TREF) in connectionwith a Light Scattering (LS) detector to determine the weight averagemolecular weight of the molecules eluted from the TREF column at a giventemperature. The combination of TREF and LS (TREF-LS) yields informationabout the breadth of the composition distribution and whether thecomonomer content increases, decreases, or is uniform across the chainsof different molecular weights.

In another patent, U.S. Pat. No. 9,290,593 ('593 patent) teaches thatthe term “BOCD” is a novel terminology that is currently developed andrelates to a polymer structure. The term “BOCD structure” means astructure in which the content of the comonomer such as alpha olefins ismainly high at a high molecular weight main chain, that is, a novelstructure in which the content of a short chain branching (SCB) isincreased as moving toward the high molecular weight. The '593 patentalso teaches a BOCD Index. The BOCD Index may be defined by thefollowing equation:BOCD Index=(Content of SCB at the high molecular weight side−Content ofSCB at the low molecular weight side)/(Content of SCB at the lowmolecular weight side)wherein the “Content of SCB at the high molecular weight side” means thecontent of the SCB (the number of branches/1000 carbon atoms) includedin a polymer chain having a molecular weight of Mw of the polyolefin ormore and 1.3×Mw or less, and the “Content of SCB at the low molecularweight side” means the content of the SCB (the number of branches/1000carbon atoms) included in a polymer chain having a molecular weight of0.7×Mw of the polyolefin or more and less than Mw. The BOCD Indexdefined by equation above may be in the range of 1 to 5, preferably 2 to4, more preferably 2 to 3.5. See, also, FIGS. 1 and 2 of the '593 patent(characterizing BOCD polymer structures using GPC-FTIR data).

BOCD behavior in a polymer composition has been associated with a goodbalance of mechanical and optical properties and has been an importantgoal in the development of new polymer products. For example, Linear LowDensity Polyethylene (LLDPE) film applications and products strive for agood balance of stiffness, toughness, optical properties (e.g., haze andgloss) and processability. For some LLDPE film applications, sealingperformance is also important. Sealing performance is affected mainly bydensity, it improves as density gets lower, but density has the oppositeeffect on stiffness. Therefore, to achieve a balanced performance, thereis usually a trade-off between stiffness and sealing performance. Thus,to improve sealing performance while maintaining good stiffness remainsa challenge. Past efforts have shown that namely molecular weightdistribution and comonomer distribution interdependence (MWD×CD) has astrong effect on sealing performance, with narrow CD resin bymetallocene catalyst outperforming broad CD resin by conventionalcatalysts. Other background references include U.S. Patent ApplicationPublication No. 2009/0156764 and U.S. Pat. Nos. 7,119,153, 7,547,754,7,572,875, 7,625,982, 8,383,754, 8,691,715, 8,722,567, 8,846,841,8,940,842, 9,006,367, 9,096,745, 9,115,229, 9,181,369, 9,181,370,9,217,049, 9,334,350, WO 2015/123164, and U.S. Pat. No. 9,447,265.

Thus, there is a need for polyethylene compositions that can exhibit,for example, BCD or BOCD behavior to produce LLDPE film products orother useful articles with a good balance of one or more of highstiffness, toughness and sealing performance, as well as good opticalproperties (e.g., haze and gloss).

SUMMARY OF THE INVENTION

In a class of embodiments, the invention provides for a method forproducing a polyolefin by contacting a first composition and a secondcomposition in a line to form a third composition, which is fed to agas-phase fluidized bed reactor, along with other feed components,including hydrogen, ethylene, and a one or more C₃ to C₁₂ alpha olefincomonomer(s). The third composition and the other reactor feedcomponents are then exposed to polymerization conditions in thegas-phase fluidized bed reactor in order to obtain a polyolefin.

The first composition is a slurry formed from the combination of a firstbimetallic catalyst and a diluent. The first bimetallic catalyst is thecontact product of i) a hafnocene catalyst, ii) a zirconocene catalyst,iii) a support, and iv) an activator, wherein the mol ratio of hafniumto zirconium is from 95:5 to 70:30.

The second composition comprises a zirconocene catalyst, which may bethe same or different from the zirconocene catalyst in the firstbimetallic catalyst, and a solvent. This in the zirconocene catalyst isdissolved in the solvent to form a solution.

The third composition comprises a second bimetallic catalyst having molratio of hafnium to zirconium of from 85:15 to 50:50. The thirdcomposition is formed by mixing the first composition and the secondcomposition in a feed line.

The polymerization conditions in some embodiments include: a hydrogenconcentration in the range of from 50 ppm to 2000 ppm, an ethyleneconcentration in the range of from 35 mol % to 95 mol %; a comonomerconcentration in the range of from 0.2 mol % to 2 mol %; a reactorpressure in the range of from 200 psig to 500 psig; and a reactortemperature in the range of from 100° F. to 250° F.

In a another class of embodiments, the invention provides for a methodfor producing a polyolefin by feeding a first bimetallic catalyst indiluent as a slurry to a gas-phase fluidized bed reactor, along withother feed components, including hydrogen, ethylene, a one or more C₃ toC₁₂ alpha olefin comonomer(s), and a second bimetallic catalyst. Thefirst bimetallic catalyst in diluent as a slurry and the other reactorfeed components are then exposed to polymerization conditions in thegas-phase fluidized bed reactor in order to obtain a polyolefin. Thefirst bimetallic catalyst and the second bimetallic catalyst are thesame or different and are each the contact product of i) a hafnocenecatalyst, ii) a zirconocene catalyst, iii) a support, and iv) anactivator, wherein the mol ratio of hafnium to zirconium is from 95:5 to70:30.

In some embodiments, the polyolefin so produced is a polyethylenecomposition comprising at least 65 wt % ethylene derived units and from0.1 to 35 wt % of C₃-C₁₂ olefin comonomer derived units, based upon thetotal weight of the polyethylene composition; wherein the polyethylenecomposition has:

a) an RCI,m of 100 kg/mol or greater, such as 150 kg/mol or greater;

and one or more of the following:

b) a density of from 0.890 g/cm³ to 0.940 g/cm³;

c) a melt index (MI) of from 0.1 g/10 min to 30 g/10 min;

d) a melt index ratio (I₂₁/I₂) of from 10 to 90;

e) an M_(w)/M_(n) of from 2 to 16;

f) an M_(z)/M_(w) of from 2.5 to 5.0;

g) an M_(z)/M_(n) of from 10 to 50; and

h) a g′(vis) of 0.90 or greater.

In another class of embodiments, the invention provides for polymersmade from the disclosed processes.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1a and FIG. 1b are illustrations of polyolefin's compositiondistribution characteristics: FIG. 1a is Polyolefin with narrowcomposition distribution (NCD); FIG. 1b is Polyolefin with BroadOrthogonal Composition Distribution (BOCD).

FIG. 2 is a schematic of a gas-phase reactor system, according to oneembodiment.

FIG. 3 is a schematic of a nozzle, according to one embodiment.

DETAILED DESCRIPTION

Before the present compounds, components, compositions, and/or methodsare disclosed and described, it is to be understood that unlessotherwise indicated this invention is not limited to specific compounds,components, compositions, reactants, reaction conditions, ligands,metallocene structures, catalyst structures, or the like, as such mayvary, unless otherwise specified. It is also to be understood that theterminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting.

In several classes of embodiments of the invention, the presentdisclosure is directed to catalyst systems and their use inpolymerization processes to produce polyolefin polymers such aspolyethylene polymers and polypropylene polymers. In another class ofembodiments, the present disclosure is directed to polymerizationprocesses to produce polyolefin polymers from catalyst systemscomprising the product of the combination of one or more olefinpolymerization catalysts, at least one activator, and at least onesupport.

In particular, the present disclosure is directed to a polymerizationprocess to produce a polyethylene polymer, the process comprisingcontacting a catalyst system comprising the product of the combinationof two or more metallocene catalysts, at least one activator, and atleast one support, with ethylene and one or more C₃-C₁₀ alpha-olefincomonomers under polymerizable conditions.

Definitions

For purposes of this invention and the claims hereto, the numberingscheme for the Periodic Table Groups is according to the new notation ofthe IUPAC Periodic Table of Elements.

As used herein, “olefin polymerization catalyst(s) refers to anycatalyst, typically an organometallic complex or compound that iscapable of coordination polymerization addition where successivemonomers are added in a monomer chain at the organometallic activecenter.

The terms “substituent,” “radical,” “group,” and “moiety” may be usedinterchangeably.

As used herein, and unless otherwise specified, the term “C_(n)” meanshydrocarbon(s) having n carbon atom(s) per molecule, wherein n is apositive integer.

As used herein, and unless otherwise specified, the term “hydrocarbon”means a class of compounds containing hydrogen bound to carbon, andencompasses (i) saturated hydrocarbon compounds, (ii) unsaturatedhydrocarbon compounds, and (iii) mixtures of hydrocarbon compounds(saturated and/or unsaturated), including mixtures of hydrocarboncompounds having different values of n.

For purposes of this invention and claims thereto, unless otherwiseindicated, the term “substituted” means that a hydrogen group has beenreplaced with a heteroatom, or a heteroatom containing group (such ashalogen (such as Br, Cl, F or I) or at least one functional group suchas NR*₂, OR*, SeR*, TeR*, PR*₂, AsR*₂, SbR*₂, SR*, BR*₂, SiR*₃, GeR*₃,SnR*₃, PbR*₃, and the like, or where at least one heteroatom has beeninserted within a hydrocarbyl ring), or a hydrocarbyl group, except thatsubstituted hydrocarbyl is a hydrocarbyl in which at least one hydrogenatom of the hydrocarbyl has been substituted with at least oneheteroatom or heteroatom containing group, such as halogen (such as Br,Cl, F or I) or at least one functional group such as NR*₂, OR*, SeR*,TeR*, PR*₂, AsR*₂, SbR*₂, SR*, BR*₂, SiR*₃, GeR*₃, SnR*₃, PbR*₃, and thelike, or where at least one heteroatom has been inserted within ahydrocarbyl ring.

The terms “hydrocarbyl radical,” “hydrocarbyl,” “hydrocarbyl group,”“alkyl radical,” and “alkyl” are used interchangeably throughout thisdocument. Likewise, the terms “group,” “radical,” and “substituent,” arealso used interchangeably in this document. For purposes of thisdisclosure, “hydrocarbyl radical” is defined to be C₁-C₁₀₀ radicals,that may be linear, branched, or cyclic, and when cyclic, aromatic ornon-aromatic. Examples of such radicals include, but are not limited to,methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl,tert-butyl, pentyl, iso-amyl, hexyl, octyl cyclopropyl, cyclobutyl,cyclopentyl, cyclohexyl, cyclooctyl, and the like including theirsubstituted analogues.

As used herein, and unless otherwise specified, the term “alkyl” refersto a saturated hydrocarbon radical having from 1 to 12 carbon atoms(i.e., C₁-C₁₂ alkyl), particularly from 1 to 8 carbon atoms (i.e., C₁-C₈alkyl), particularly from 1 to 6 carbon atoms (i.e., C₁-C₆ alkyl), andparticularly from 1 to 4 carbon atoms (i.e., C₁-C₄ alkyl). Examples ofalkyl groups include, but are not limited to, methyl, ethyl, propyl,butyl, pentyl, hexyl, heptyl, octyl, decyl, and so forth. The alkylgroup may be linear, branched or cyclic. “Alkyl” is intended to embraceall structural isomeric forms of an alkyl group. For example, as usedherein, propyl encompasses both n-propyl and isopropyl; butylencompasses n-butyl, sec-butyl, isobutyl and tert-butyl and so forth. Asused herein, “C₁ alkyl” refers to methyl (—CH₃), “C₂ alkyl” refers toethyl (—CH₂CH₃), “C₃ alkyl” refers to propyl (—CH₂CH₂CH₃) and “C₄ alkyl”refers to butyl (e.g., —CH₂CH₂CH₂CH₃, —(CH₃)CHCH₂CH₃, —CH₂CH(CH₃)₂,etc.). Further, as used herein, “Me” refers to methyl, and “Et” refersto ethyl, “i-Pr” refers to isopropyl, “t-Bu” refers to tert-butyl, and“Np” refers to neopentyl.

As used herein, and unless otherwise specified, the term “alkylene”refers to a divalent alkyl moiety containing 1 to 12 carbon atoms (i.e.,C₁-C₁₂ alkylene) in length and meaning the alkylene moiety is attachedto the rest of the molecule at both ends of the alkyl unit. For example,alkylenes include, but are not limited to, —CH₂—, —CH₂CH₂—,—CH(CH₃)CH₂—, —CH₂CH₂CH₂—, etc. The alkylene group may be linear orbranched.

As used herein, and unless otherwise specified, the term “alkenyl”refers to an unsaturated hydrocarbon radical having from 2 to 12 carbonatoms (i.e., C₂-C₁₂ alkenyl), particularly from 2 to 8 carbon atoms(i.e., C₂-C₈ alkenyl), particularly from 2 to 6 carbon atoms (i.e.,C₂-C₆ alkenyl), and having one or more (e.g., 2, 3, etc.) carbon-carbondouble bonds. The alkenyl group may be linear, branched or cyclic.Examples of alkenyls include, but are not limited to ethenyl (vinyl),2-propenyl, 3-propenyl, 1,4-pentadienyl, 1,4-butadienyl, 1-butenyl,2-butenyl and 3-butenyl. “Alkenyl” is intended to embrace all structuralisomeric forms of an alkenyl. For example, butenyl encompasses1,4-butadienyl, 1-butenyl, 2-butenyl and 3-butenyl, etc.

As used herein, and unless otherwise specified, the term “alkenylene”refers to a divalent alkenyl moiety containing 2 to about 12 carbonatoms (i.e., C₂-C₁₂ alkenylene) in length and meaning that the alkylenemoiety is attached to the rest of the molecule at both ends of the alkylunit. For example, alkenylenes include, but are not limited to, —CH═CH—,—CH═CHCH₂—, —CH═CH═CH—, —CH₂CH₂CH═CHCH₂—, etc. The alkenylene group maybe linear or branched.

As used herein, and unless otherwise specified, the term “alkynyl”refers to an unsaturated hydrocarbon radical having from 2 to 12 carbonatoms (i.e., C₂-C₁₂ alkynyl), particularly from 2 to 8 carbon atoms(i.e., C₂-C₈ alkynyl), particularly from 2 to 6 carbon atoms (i.e.,C₂-C₆ alkynyl), and having one or more (e.g., 2, 3, etc.) carbon-carbontriple bonds. The alkynyl group may be linear, branched or cyclic.Examples of alkynyls include, but are not limited to ethynyl,1-propynyl, 2-butynyl, and 1,3-butadiynyl. “Alkynyl” is intended toembrace all structural isomeric forms of an alkynyl. For example,butynyl encompasses 2-butynyl, and 1,3-butadiynyl and propynylencompasses 1-propynyl and 2-propynyl (propargyl).

As used herein, and unless otherwise specified, the term “alkynylene”refers to a divalent alkynyl moiety containing 2 to about 12 carbonatoms (i.e., C₂-C₁₂ alkenylene) in length and meaning that the alkylenemoiety is attached to the rest of the molecule at both ends of the alkylunit. For example, alkenylenes include, but are not limited to, —C≡C—,—C≡CCH₂—, —C≡CCH₂C≡C—, —CH₂CH₂C≡CCH₂—. The alkynylene group may belinear or branched.

As used herein, and unless otherwise specified, the term “alkoxy” refersto —O— alkyl containing from 1 to about 10 carbon atoms. The alkoxy maybe straight-chain or branched-chain. Non-limiting examples includemethoxy, ethoxy, propoxy, butoxy, isobutoxy, tert-butoxy, pentoxy, andhexoxy. “C₁ alkoxy” refers to methoxy, “C₂ alkoxy” refers to ethoxy, “C₃alkoxy” refers to propoxy and “C₄ alkoxy” refers to butoxy. Further, asused herein, “OMe” refers to methoxy and “OEt” refers to ethoxy.

As used herein, and unless otherwise specified, the term “aromatic”refers to unsaturated cyclic hydrocarbons having a delocalizedconjugated π system and having from 5 to 20 carbon atoms (aromaticC₅-C₂₀ hydrocarbon), particularly from 5 to 12 carbon atoms (aromaticC₅-C₁₂ hydrocarbon), and particularly from 5 to 10 carbon atoms(aromatic C₅-C₁₂ hydrocarbon). Exemplary aromatics include, but are notlimited to benzene, toluene, xylenes, mesitylene, ethylbenzenes, cumene,naphthalene, methylnaphthalene, dimethylnaphthalenes, ethylnaphthalenes,acenaphthalene, anthracene, phenanthrene, tetraphene, naphthacene,benzanthracenes, fluoranthrene, pyrene, chrysene, triphenylene, and thelike, and combinations thereof.

Unless otherwise indicated, where isomers of a named alkyl, alkenyl,alkoxy, or aryl group exist (e.g., n-butyl, iso-butyl, sec-butyl, andtert-butyl) reference to one member of the group (e.g., n-butyl) shallexpressly disclose the remaining isomers (e.g., iso-butyl, sec-butyl,and tert-butyl) in the family. Likewise, reference to an alkyl, alkenyl,alkoxide, or aryl group without specifying a particular isomer (e.g.,butyl) expressly discloses all isomers (e.g., n-butyl, iso-butyl,sec-butyl, and tert-butyl).

As used herein, the term “hydroxyl” refers to an —OH group.

As used herein, “oxygenate” refers to a saturated, unsaturated, orpolycyclic cyclized hydrocarbon radical containing from 1 to 40 carbonatoms and further containing one or more oxygen heteroatoms.

As used herein, “aluminum alkyl adducts” refers to the reaction productof aluminum alkyls and/or alumoxanes with quenching agents, such aswater and/or methanol.

An “olefin,” alternatively referred to as “alkene,” is a linear,branched, or cyclic compound of carbon and hydrogen having at least onedouble bond. For purposes of this specification and the claims appendedthereto, when a polymer or copolymer is referred to as comprising anolefin, the olefin present in such polymer or copolymer is thepolymerized form of the olefin. For example, when a copolymer is said tohave an “ethylene” content of 35 wt % to 55 wt %, it is understood thatthe mer unit in the copolymer is derived from ethylene in thepolymerization reaction and said derived units are present at 35 wt % to55 wt %, based upon the weight of the copolymer.

A “polymer” has two or more of the same or different mer units. A“homopolymer” is a polymer having mer units that are the same. A“copolymer” is a polymer having two or more mer units that are distinctor different from each other. A “terpolymer” is a polymer having threemer units that are distinct or different from each other. “Distinct” or“different” as used to refer to mer units indicates that the mer unitsdiffer from each other by at least one atom or are differentisomerically. Accordingly, the definition of copolymer, as used herein,includes terpolymers and the like. An “ethylene polymer” or “ethylenecopolymer” is a polymer or copolymer comprising at least 50 mol %ethylene derived units, a “propylene polymer” or “propylene copolymer”is a polymer or copolymer comprising at least 50 mol % propylene derivedunits, and so on.

“Polymerizable conditions” refer those conditions including a skilledartisan's selection of temperature, pressure, reactant concentrations,optional solvent/diluents, reactant mixing/addition parameters, andother conditions within at least one polymerization reactor that areconducive to the reaction of one or more olefin monomers when contactedwith an activated olefin polymerization catalyst to produce the desiredpolyolefin polymer through typically coordination polymerization.

The term “continuous” means a system that operates without interruptionor cessation. For example a continuous process to produce a polymerwould be one where the reactants are continually introduced into one ormore reactors and polymer product is continually withdrawn.

A “catalyst composition” or “catalyst system” is the combination of atleast two catalyst compounds, a support material, an optional activator,and an optional co-activator. For the purposes of this invention and theclaims thereto, when catalyst systems or compositions are described ascomprising neutral stable forms of the components, it is well understoodby one of ordinary skill in the art, that the ionic form of thecomponent is the form that reacts with the monomers to produce polymers.When it is used to describe such after activation, it means the support,the activated complex, and the activator or other charge-balancingmoiety. The transition metal compound may be neutral as in aprecatalyst, or a charged species with a counter ion as in an activatedcatalyst system.

Coordination polymerization is an addition polymerization in whichsuccessive monomers are added to or at an organometallic active centerto create and/or grow a polymer chain.

The terms “cocatalyst” and “activator” are used herein interchangeablyand are defined to be any compound which can activate any one of thecatalyst compounds herein by converting the neutral catalyst compound toa catalytically active catalyst compound cation.

The term “contact product” or “the product of the combination of” isused herein to describe compositions wherein the components arecontacted together in any order, in any manner, and for any length oftime. For example, the components can be contacted by blending ormixing. Further, contacting of any component can occur in the presenceor absence of any other component of the compositions described herein.Combining additional materials or components can be done by any suitablemethod. Further, the term “contact product” includes mixtures, blends,solutions, slurries, reaction products, and the like, or combinationsthereof. Although “contact product” can include reaction products, it isnot required for the respective components to react with one another orreact in the manner as theorized. Similarly, the term “contacting” isused herein to refer to materials which may be blended, mixed, slurried,dissolved, reacted, treated, or otherwise contacted in some othermanner.

“BOCD” refers to a Broad Orthogonal Composition Distribution in whichthe comonomer of a copolymer is incorporated predominantly in the highmolecular weight chains or species of a polyolefin polymer orcomposition. The distribution of the short chain branches can bemeasured, for example, using Temperature Raising Elution Fractionation(TREF) in connection with a Light Scattering (LS) detector to determinethe weight average molecular weight of the molecules eluted from theTREF column at a given temperature. The combination of TREF and LS(TREF-LS) yields information about the breadth of the compositiondistribution and whether the comonomer content increases, decreases, oris uniform across the chains of different molecular weights of polymerchains. BOCD has been described, for example, in U.S. Pat. No.8,378,043, Col. 3, line 34, bridging Col. 4, line 19, and U.S. Pat. No.8,476,392, line 43, bridging Col. 16, line 54.

The breadth of the composition distribution is characterized by theT₇₅-T₂₅ value, wherein T₂₅ is the temperature at which 25% of the elutedpolymer is obtained and T₇₅ is the temperature at which 75% of theeluted polymer is obtained in a TREF experiment as described herein. Thecomposition distribution is further characterized by the F₈₀ value,which is the fraction of polymer that elutes below 80° C. in a TREF-LSexperiment as described herein. A higher F₈₀ value indicates a higherfraction of comonomer in the polymer molecule. An orthogonal compositiondistribution is defined by a M₆₀/M₉₀ value that is greater than 1,wherein M₆₀ is the molecular weight of the polymer fraction that elutesat 60° C. in a TREF-LS experiment and M₉₀ is the molecular weight of thepolymer fraction that elutes at 90° C. in a TREF-LS experiment asdescribed herein.

In a class of embodiments, the polymers as described herein may have aBOCD characterized in that the T₇₅-T₂₅ value is 1 or greater, 2.0 orgreater, 2.5 or greater, 4.0 or greater, 5.0 or greater, 7.0 or greater,10.0 or greater, 11.5 or greater, 15.0 or greater, 17.5 or greater, 20.0or greater, 25.0 or greater, 30.0 or greater, 35.0 or greater, 40.0 orgreater, or 45.0 or greater, wherein T₂₅ is the temperature at which 25%of the eluted polymer is obtained and T₇₅ is the temperature at which75% of the eluted polymer is obtained in a TREF experiment as describedherein.

The polymers as described herein may further have a BOCD characterizedin that M₆₀/M₉₀ value is 1.5 or greater, 2.0 or greater, 2.25 orgreater, 2.50 or greater, 3.0 or greater, 3.5 or greater, 4.0 orgreater, 4.5 or greater, or 5.0 or greater, wherein M₆₀ is the molecularweight of the polymer fraction that elutes at 60° C. in a TREF-LSexperiment and M₉₀ is the molecular weight of the polymer fraction thatelutes at 90° C. in a TREF-LS experiment as described herein.

Olefin Polymerization Catalysts

Metallocene Catalysts

The catalyst system useful herein is a mixed metallocene catalyst systemcomprising two or more different metallocene catalyst compounds, atleast one activator, and at least one support. A first metallocenecatalyst compound is one or more hafnocene catalyst compoundsrepresented by formula (A1) and/or formula (A2) below. A secondmetallocene catalyst compound is one or more zirconocene catalystcompounds represented by formula (B) below.

Hafnocenes

In some embodiments, the first metallocene catalyst compound isrepresented by the formula (A1):Cp^(A)Cp^(B)M′X′_(n)  (A1)wherein,

Cp^(A) is a cyclopentadienyl group which may be substituted orunsubstituted, provided that Cp^(A) is substituted with at least one R**group, where R** is a group containing at least three carbon or siliconatoms, preferably R** is a C₃ to C₁₂ alky group, preferably R** is alinear C₃ to C₁₂ alkyl group (such as n-propyl, n-butyl, n-pentyl,n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl or n-dodecyl),and Cp^(A) is optionally also independently substituted by one, two,three, or four R″ groups;

-   -   Cp^(B) is a cyclopentadienyl group which may be substituted or        unsubstituted, substituted by one, two, three, four, or five R″        groups or R** groups;    -   M′ is Hf;    -   each X′ is, independently, a univalent anionic ligand, or two X′        are joined and bound to the metal atom to form a metallocycle        ring, or two X′ are joined to form a chelating ligand, a diene        ligand, or an alkylidene ligand (preferably each X′ is        independently, halogen or C₁ to C₁₂ alkyl or C₅ to C₁₂ aryl,        such as Br, Cl, I, Me, Et, Pr, Bu, Ph);    -   n is 0, 1, 2, 3, or 4, preferably n is 2; and    -   each R″ is independently selected from the group consisting of        hydrocarbyl, substituted hydrocarbyl, heteroatom, or heteroatom        containing group.

In a preferred embodiment of the invention, Cp^(A) and Cp^(B) are eachsubstituted with at least one R** group, preferably n-propyl or n-butyl.

In a preferred embodiment of the invention, each R″ is independentlyselected from the group consisting of alkyl, substituted alkyl,heteroalkyl, alkenyl, substituted alkenyl, heteroalkenyl, alkynyl,substituted alkynyl, heteroalkynyl, alkoxy, aryloxy, alkylthio,arylthio, aryl, substituted aryl, heteroaryl, aralkyl, aralkylene,alkaryl, alkarylene, haloalkyl, haloalkenyl, haloalkynyl, heteroalkyl,heterocycle, heteroaryl, a heteroatom-containing group, hydrocarbyl,substituted hydrocarbyl, heterohydrocarbyl, silyl, boryl, phosphino,phosphine, amino, amine, ether, and thioether.

In a preferred embodiment of the invention, each R″ is independentlyhydrogen, or a substituted C₁ to C₁₂ hydrocarbyl group or anunsubstituted C₁ to C₁₂ hydrocarbyl group, preferably R″ is a C₁ to C₂₀substituted or unsubstituted hydrocarbyl, preferably a substituted C₁ toC₁₂ hydrocarbyl group or an unsubstituted C₁ to C₁₂ hydrocarbyl group,preferably methyl, ethyl, propyl, butyl, pentyl, hexyl, or an isomerthereof.

More particular, non-limiting examples of R″ include methyl, ethyl,propyl, butyl, pentyl, hexyl, cyclopentyl, cyclohexyl, benzyl, phenyl,methylphenyl, and tert-butylphenyl groups and the like, including alltheir isomers, for example, tertiary-butyl, isopropyl, and the like.

Preferably R** is a C₃ to C₄ hydrocarbyl (preferably n-propyl orn-butyl).

In a preferred embodiment of the invention, each X is, independently,selected from the group consisting of hydrocarbyl radicals having from 1to 20 carbon atoms, aryls, hydrides, amides, alkoxides, sulfides,phosphides, halides, dienes, amines, phosphines, ethers, and acombination thereof (two X's may form a part of a fused ring or a ringsystem), preferably each X is independently selected from halides, arylsand C₁ to C₅ alkyl groups, preferably each X is a phenyl, methyl, ethyl,propyl, butyl, pentyl, bromo, or chloro group. Preferably, each X is,independently, a halide, a hydride, an alkyl group, an alkenyl group oran arylalkyl group.

Compounds useful as the first metallocene are disclosed in U.S. Pat. No.6,242,545, which is incorporated by reference herein.

In at least one embodiment, the first metallocene catalyst representedby the formula: (A) produces a polyolefin having a high comonomercontent.

Preferably the first metallocene(s) are selected from the groupconsisting of: bis(n-propylcyclopentadienyl)hafnium dichloride,bis(n-propylcyclopentadienyl)hafnium dimethyl,(n-propylcyclopentadienyl, pentamethylcyclopentadienyl)hafniumdichloride, (n-propylcyclopentadienyl,pentamethylcyclopentadienyl)hafnium dimethyl, (n-propylcyclopentadienyl,tetramethylcyclopentadienyl)hafnium dichloride,(n-propylcyclopentadienyl, tetramethylcyclopentadienyl)hafnium dimethyl,bis(cyclopentadienyl)hafnium dimethyl,bis(n-butylcyclopentadienyl)hafnium dichloride,bis(n-butylcyclopentadienyl)hafnium dimethyl, andbis(1-methyl-3-n-butylcyclopentadienyl)hafnium dimethyl.

For purposes of this invention, one catalyst compound is considereddifferent from another if they differ by at least one atom. For example,“bisindenyl zirconium dichloride” is different from“(indenyl)(2-methylindenyl) zirconium dichloride” which is differentfrom “(indenyl)(2-methylindenyl) hafnium dichloride.” Catalyst compoundsthat differ only by isomer are considered the same for purposes if thisinvention, e.g., rac-dimethylsilylbis(2-methyl 4-phenylindenyl)hafniumdimethyl is considered to be the same as meso-dimethylsilylbis(2-methyl4-phenylindenyl)hafnium dimethyl.

In some embodiments, the first metallocene catalyst compound isrepresented by the formula (A2):

(i) a metallocene catalyst represented by the formula (A2):

where:M is Hafnium;each R¹, R², and R⁴ is independently hydrogen, alkoxide, or a C₁ to C₄₀substituted or unsubstituted hydrocarbyl group (preferably a C₁ to C₂₀substituted or unsubstituted hydrocarbyl group);R³ is independently hydrogen, alkoxide or a C₁ to C₄₀ substituted orunsubstituted hydrocarbyl group (preferably a C₁ to C₂₀ substituted orunsubstituted hydrocarbyl group), or is —R²⁰—SiR′₃ or —R²⁰—CR′₃ whereR²⁰ is hydrogen, or a C₁ to C₄ hydrocarbyl, and each R′ is independentlya C₁ to C₂₀ substituted or unsubstituted hydrocarbyl, provided that atleast one R′ is not H;each R⁷, R⁸, and R¹⁰ is independently hydrogen, alkoxide or a C₁ to C₄₀substituted or unsubstituted hydrocarbyl group (preferably a C₁ to C₂₀substituted or unsubstituted hydrocarbyl group);R⁹ is —R²⁰—SiR′₃ or —R²⁰—CR′₃ where R²⁰ is hydrogen or a C₁ to C₄hydrocarbyl (preferably R²⁰ is CH₂), and each R′ is independently a C₁to C₂₀ substituted or unsubstituted hydrocarbyl, (preferably R′ isalkyl, such as Me, or aryl, such as phenyl), provided that at least oneR′ is not H, alternately 2 R′ are not H, alternately 3 R′ are not H;T is a bridging group, such as CR²¹R²², where R²¹ and R²² areindependently hydrogen, halogen, or a C₁-C₂₀ containing hydrocarbylgroup (for example, linear hydrocarbyl group), substituted hydrocarbylgroup, and optionally R²¹ and R²² join to form a substituted orunsubstituted, saturated, partially unsaturated or aromatic, cyclic orpolycyclic substituent, optionally R²¹ and R²² are the same ordifferent; andeach X is, independently, a univalent anionic ligand, or two X arejoined and bound to the metal atom to form a metallocycle ring, or two Xare joined to form a chelating ligand, a diene ligand, or an alkylideneligand (preferably halogen or C1 to C12 alkyl or aryl, such as Cl, Me,Et, Ph).

In a preferred embodiment of the invention, M is Hf, alternately M isZr.

In a preferred embodiment of the invention, each R¹, R², and R⁴ isindependently hydrogen, or a substituted C₁ to C₁₂ hydrocarbyl group oran unsubstituted C₁ to C₁₂ hydrocarbyl group, preferably hydrogen,methyl, ethyl, propyl, butyl, pentyl, hexyl, or an isomer thereof.

In a preferred embodiment of the invention, each R³ is independentlyhydrogen, or a substituted C₁ to C₁₂ hydrocarbyl group or anunsubstituted C₁ to C₁₂ hydrocarbyl group, preferably hydrogen, methyl,ethyl, propyl, butyl, pentyl, hexyl, or an isomer thereof or R³ is—R²⁰—SiR′₃ or —R²⁰—CR′₃ where R²⁰ is a C₁ to C₄ hydrocarbyl (preferablymethyl, ethyl, propyl, butyl), and R′ is a C₁ to C₂₀ substituted orunsubstituted hydrocarbyl, preferably a substituted C₁ to C₁₂hydrocarbyl group or an unsubstituted C₁ to C₁₂ hydrocarbyl group,preferably methyl, ethyl, propyl, butyl, pentyl, hexyl, or an isomerthereof.

In a preferred embodiment of the invention, each R⁷, R⁸, and R¹⁰ isindependently hydrogen, or a substituted C₁ to C₁₂ hydrocarbyl group oran unsubstituted C₁ to C₁₂ hydrocarbyl group, preferably hydrogen,methyl, ethyl, propyl, butyl, pentyl, hexyl, or an isomer thereof.

In a preferred embodiment of the invention, R⁹, is —R²⁰—SiR′₃ or—R²⁰—CR′₃ where R²⁰ is a C₁ to C₄ hydrocarbyl (preferably methyl, ethyl,propyl, butyl), and R′ is a C₁ to C₂₀ substituted or unsubstitutedhydrocarbyl, preferably a substituted C₁ to C₁₂ hydrocarbyl group or anunsubstituted C₁ to C₁₂ hydrocarbyl group, preferably methyl, ethyl,propyl, butyl, pentyl, hexyl, or an isomer thereof.

Alternately, R⁹ and optionally R³ are, independently, —R²⁰—CMe₃, or—R²⁰—SiMe₃ where R²⁰ is a C₁ to C₄ hydrocarbyl (preferably methyl,ethyl, propyl, butyl), preferably —CH₂—CMe₃, or —CH₂—SiMe₃.

Alternately, each X may be, independently, a halide, a hydride, an alkylgroup, an alkenyl group or an arylalkyl group.

Alternately, each X is, independently, selected from the groupconsisting of hydrocarbyl radicals having from 1 to 20 carbon atoms,aryls, hydrides, amides, alkoxides, sulfides, phosphides, halides,dienes, amines, phosphines, ethers, and a combination thereof (two X'smay form a part of a fused ring or a ring system), preferably each X isindependently selected from halides, aryls and C₁ to C₅ alkyl groups,preferably each X is a phenyl, methyl, ethyl, propyl, butyl, pentyl,bromo, or chloro group.

Preferably, T is a bridging group containing at least one Group 13, 14,15, or 16 element, in particular boron or a Group 14, 15 or 16 element.Examples of suitable bridging groups include P(═S)R′, P(═Se)R′, P(═O)R,R′₂C, R′₂Si, R′₂Ge, R′₂CCR′₂, R′₂CCR′₂CR′₂, R′₂CCR′₂CR′₂CR′₂, R′C═CR′,R′C═CR′CR′₂, R′₂CCR′═CR′CR′₂, R′C═CR′CR′═CR′, R′C═CR′CR′₂CR′₂,R′₂CSiR′₂, R′₂SiSiR′₂, R′₂SiOSiR′₂, R′₂CSiR′₂CR′₂, R′₂SiCR′₂SiR′₂,R′C═CR′SiR′₂, R′₂CGeR′₂, R′₂GeGeR′₂, R′₂CGeR′₂CR′₂, R′₂GeCR′₂GeR′₂,R′₂SiGeR′₂, R′C═CR′GeR′₂, R′B, R′₂C—BR′, R′₂C—BR′—CR′₂, R′₂C—O—CR′₂,R′₂CR′₂C—O—CR′₂CR′₂, R′₂C—O—CR′₂CR′₂, R′₂C—O—CR′═CR′, R′₂C—S—CR′₂,R′₂CR′₂C—S—CR′₂CR′₂, R′₂C—S—CR′₂CR′₂, R′₂C—S—CR′═CR′, R′₂C—Se—CR′₂,R′₂CR′₂C—Se—CR′₂CR′₂, R′₂C—Se—CR′₂CR′₂, R′₂C—Se—CR′═CR′, R′₂C—N═CR′,R′₂C—NR′—CR′₂, R′₂C—NR′—CR′₂CR′₂, R′₂C—NR′—CR′═CR′,R′₂CR′₂C—NR′—CR′₂CR′₂, R′₂C—P═CR′, R′₂C—PR′—CR′₂, O, S, Se, Te, NR′,PR′, AsR′, SbR′, O—O, S—S, R′N—NR′, R′P—PR′, O—S, O—NR′, O—PR′, S—NR′,S—PR′, and R′N—PR′, where R′ is hydrogen or a C₁-C₂₀ containinghydrocarbyl, substituted hydrocarbyl, halocarbyl, substitutedhalocarbyl, silylcarbyl or germylcarbyl substituent and optionally twoor more adjacent R′ may join to form a substituted or unsubstituted,saturated, partially unsaturated or aromatic, cyclic or polycyclicsubstituent. Preferred examples for the bridging group T include CH₂,CH₂CH₂, SiMe₂, SiPh₂, SiMePh, Si(CH₂)₃, Si(CH₂)₄, O, S, NPh, PPh, NMe,PMe, NEt, NPr, NBu, PEt, PPr, Me₂SiOSiMe₂, and PBu.

In a preferred embodiment of the invention in any embodiment of anyformula described herein, T is represented by the formula R^(a) ₂J or(R^(a) ₂J)₂, where J is C, Si, or Ge, and each Ra is, independently,hydrogen, halogen, C₁ to C₂₀ hydrocarbyl (such as methyl, ethyl, propyl,butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, or dodecyl)or a C₁ to C₂ o substituted hydrocarbyl, and two Ra can form a cyclicstructure including aromatic, partially saturated, or saturated cyclicor fused ring system. Preferably, T is a bridging group comprisingcarbon or silica, such as dialkylsilyl, preferably T is selected fromCH₂, CH₂CH₂, C(CH₃)₂, SiMe₂, SiPh₂, SiMePh, silylcyclobutyl (Si(CH₂)₃),(Ph)₂C, (p-(Et)₃SiPh)₂C, Me₂SiOSiMe₂, and cyclopentasilylene (Si(CH₂)₄).

In a preferred embodiment of the invention, the molar ratio of rac tomeso in the catalyst compound is from 1:1 to 100:1, preferably 5:1 to90:1, preferably 7:1 to 80:1, preferably 5:1 or greater, or 7:1 orgreater, or 20:1 or greater, or 30:1 or greater, or 50:1 or greater. Inan embodiment of the invention, the catalyst comprises greater than 55mol % of the racemic isomer, or greater than 60 mol % of the racemicisomer, or greater than 65 mol % of the racemic isomer, or greater than70 mol % of the racemic isomer, or greater than 75 mol % of the racemicisomer, or greater than 80 mol % of the racemic isomer, or greater than85 mol % of the racemic isomer, or greater than 90 mol % of the racemicisomer, or greater than 92 mol % of the racemic isomer, or greater than95 mol % of the racemic isomer, or greater than 97 mol % of the racemicisomer, based on the total amount of the racemic and meso isomer, ifany, formed. In a particular embodiment of the invention, themetallocene transition metal compound formed consists essentially of theracemic isomer.

Amounts of rac and meso isomers are determined by proton NMR. 1H NMRdata are collected at 23° C. in a 5 mm probe using a 400 MHz Brukerspectrometer with deuterated methylene chloride. (Note that some of theexamples herein may use deuterated benzene, but for purposes of theclaims, methylene chloride shall be used.) Data is recorded using amaximum pulse width of 45°, 5 seconds between pulses and signalaveraging 16 transients. The spectrum is normalized to protonatedmethylene chloride in the deuterated methylene chloride, which isexpected to show a peak at 5.32 ppm.

Catalyst compounds that are particularly useful in this inventioninclude one or more of: rac/meso Me₂Si(Me₃SiCH₂Cp)₂HfMe₂;racMe₂Si(Me₃SiCH₂Cp)₂HfMe₂; rac/meso Ph₂Si(Me₃SiCH₂Cp)₂HfMe₂; rac/meso(CH₂)₃Si(Me₃SiCH₂Cp)₂HfMe₂; rac/meso (CH₂)₄Si(Me₃SiCH₂Cp)₂HfMe₂;rac/meso (C₆F₅)₂Si(Me₃SiCH₂Cp)₂HfMe₂; rac/meso(CH₂)₃Si(Me₃SiCH₂Cp)₂ZrMe₂; rac/meso Me₂Ge(Me₃SiCH₂Cp)₂HfMe₂; rac/mesoMe₂Si(Me₂PhSiCH₂Cp)₂HfMe₂; rac/meso Ph₂Si(Me₂PhSiCH₂Cp)₂HfMe₂;Me₂Si(Me₄Cp)(Me₂PhSiCH₂Cp)HfMe₂; rac/meso (CH₂)₃Si(Me₂PhSiCH₂Cp)₂HfMe₂;rac/meso (CH₂)₄Si(Me₂PhSiCH₂Cp)₂HfMe₂; rac/meso(C₆F₅)₂Si(Me₂PhSiCH₂Cp)₂HfMe₂; rac/meso Me₂Ge(Me₂PhSiCH₂Cp)₂HfMe₂;rac/meso Me₂Si(MePh₂SiCH₂Cp)₂HfMe₂; rac/meso Ph₂Si(MePh₂SiCH₂Cp)₂HfMe₂;rac/meso Me₂Si(MePh₂SiCH₂Cp)₂ZrMe₂; rac/meso(CH₂)₃Si(MePh₂SiCH₂Cp)₂HfMe₂; rac/meso (CH₂)₄Si(MePh₂SiCH₂Cp)₂HfMe₂;rac/meso (C₆F₅)₂Si(MePh₂SiCH₂Cp)₂HfMe₂; rac/mesoMe₂Ge(MePh₂SiCH₂Cp)₂HfMe₂; rac/meso Me₂Si(Ph₃SiCH₂Cp)₂HfMe₂; rac/mesoPh₂Si(Ph₃SiCH₂Cp)₂HfMe₂; rac/meso Me₂Si(Ph₃SiCH₂Cp)₂ZrMe₂; rac/meso(CH₂)₃Si(Ph₃SiCH₂Cp)₂HfMe₂; rac/meso (CH₂)₄Si(Ph₃SiCH₂Cp)₂HfMe₂;rac/meso (C₆F₅)₂Si(Ph₃SiCH₂Cp)₂HfMe₂; rac/meso Me₂Ge(Ph₃SiCH₂Cp)₂HfMe₂;rac/meso Me₂Si(Cy₃SiCH₂Cp)₂HfMe₂; racMe₂Si(Cy₃SiCH₂Cp)₂HfMe₂; rac/mesoPh₂Si(Cy₃SiCH₂Cp)₂HfMe₂; rac/meso Me₂Si(Cy₃SiCH₂Cp)₂ZrMe₂; rac/meso(CH₂)₃Si(Cy₃SiCH₂Cp)₂HfMe₂; rac/meso (CH₂)₄Si(Cy₃SiCH₂Cp)₂HfMe₂;rac/meso (C₆F₅)₂Si(Cy₃SiCH₂Cp)₂HfMe₂; rac/meso Me₂Ge(Cy₃SiCH₂Cp)₂HfMe₂;rac/meso Me₂Si(Cy₂MeSiCH₂Cp)₂HfMe₂; rac/meso Ph₂Si(Cy₂MeSiCH₂Cp)₂HfMe₂;Me₂Si(Me₄Cp)(Cy₂MeSiCH₁₂Cp)HfMe₂; rac/meso(CH₂)₃Si(Cy₂MeSiCH₁₂Cp)₂HfMe₂; rac/meso (CH₂)₄Si(Cy₂MeSiCH₁₂Cp)₂HfMe₂;rac/meso (C₆F₅)₂Si(Cy₂MeSiCH₁₂Cp)₂HfMe₂; rac/mesoMe₂Ge(Cy₂MeSiCH₁₂Cp)₂HfMe₂; rac/meso Me₂Si(CyMe₂SiCH₁₂Cp)₂HfMe₂;rac/meso Ph₂Si(CyMe₂SiCH₂Cp)₂HfMe₂; rac/meso(CH₂)₃Si(CyMe₂SiCH₁₂Cp)₂HfMe₂; rac/meso (CH₂)₄Si(CyMe₂SiCH₁₂Cp)₂HfMe₂;rac/meso (C₆F₅)₂Si(CyMe₂SiCH₁₂Cp)₂HfMe₂; rac/mesoMe₂Ge(CyMe₂SiCH₁₂Cp)₂HfMe₂; rac/meso Me₂Si(Cy₂PhSiCH₁₂Cp)₂HfMe₂;rac/meso Ph₂Si(Cy₂PhSiCH₂Cp)₂HfMe₂; rac/meso(CH₂)₃Si(Cy₂PhSiCH₂Cp)₂HfMe₂; rac/meso (CH₂)₄Si(Cy₂PhSiCH₂Cp)₂HfMe₂;rac/meso (C₆F₅)₂Si(Cy₂PhSiCH₂Cp)₂HfMe₂; rac/mesoMe₂Ge(Cy₂PhSiCH₂Cp)₂HfMe₂; rac/meso Me₂Si(CyPh₂SiCH₂Cp)₂HfMe₂; rac/mesoPh₂Si(CyPh₂SiCH₂Cp)₂HfMe₂; rac/meso (CH₂)₃Si(CyPh₂SiCH₂Cp)₂HfMe₂;rac/meso (CH₂)₄Si(CyPh₂SiCH₂Cp)₂HfMe₂; rac/meso(C₆F₅)₂Si(CyPh₂SiCH₂Cp)₂HfMe₂; and rac/meso Me₂Ge(CyPh₂SiCH₂Cp)₂HfMe₂.

In a preferred embodiment in any of the processes described herein, onecatalyst compound is used, e.g., the catalyst compounds are notdifferent. For purposes of this invention, one catalyst compound isconsidered different from another if they differ by at least one atom.For example, “bisindenyl zirconium dichloride” is different from“(indenyl)(2-methylindenyl) zirconium dichloride” which is differentfrom “(indenyl)(2-methylindenyl) hafnium dichloride.” Catalyst compoundsthat differ only by isomer are considered the same for purposes if thisinvention, e.g., rac-dimethylsilylbis(2-methyl 4-phenylindenyl)hafniumdimethyl is considered to be the same as meso-dimethylsilylbis(2-methyl4-phenylindenyl)hafnium dimethyl.

Zirconocenes

Metallocene catalyst compounds useful herein are compounds differentfrom compounds represented by formulas A1 and A2 and are compoundsrepresented by the formula (B):T_(y)Cp_(m)M⁶G_(n)X⁵ _(q)wherein,each Cp is, independently, a cyclopentadienyl group (such ascyclopentadiene, indene or fluorene) which may be substituted orunsubstituted, provided that at least one Cp is an indene or fluorenegroup;M⁶ is a zirconium;G is a heteroatom group represented by the formula JR*_(z) where J is N,P, O or S, and R* is a C₁ to C₂ o hydrocarbyl group and z is 1 or 2;T is a bridging group;y is 0 or 1;X⁵ is a leaving group (such as a halide, a hydride, an alkyl group, analkenyl group or an arylalkyl group);m is 1 or 2;n is 0, 1, 2 or 3;q is 0, 1, 2, or 3; andthe sum of m+n+q is equal to the oxidation state of the transitionmetal, preferably 4. See, for example, WO 2016/094843.

In a preferred embodiment of the invention, each Cp is, independently,an indenyl group which may be substituted or unsubstituted, preferablyeach Cp is independently substituted with a C₁ to C₄₀ hydrocarbyl groupor an unsubstituted C₁ to C₄₀ hydrocarbyl group, preferably Cp is anindenyl group substituted with a C₁ to C₂₀ substituted or unsubstitutedhydrocarbyl, preferably a substituted C₁ to C₁₂ hydrocarbyl group or anunsubstituted C₁ to C₁₂ hydrocarbyl group, preferably methyl, ethyl,propyl, butyl, pentyl, hexyl, or an isomer thereof.

Preferably, T is present (e.g., y=1) and is a bridging group containingat least one Group 13, 14, 15, or 16 element, in particular boron or aGroup 14, 15 or 16 element. Examples of suitable bridging groups includeP(═S)R′, P(═Se)R′, P(═O)R′, R′₂C, R′₂Si, R′₂Ge, R′₂CCR′₂, R′₂CCR′₂CR′₂,R′₂CCR′₂CR′₂CR′₂, R′C═CR′, R′C═CR′CR′₂, R′₂CCR′═CR′CR′₂, R′C═CR′CR′═CR′,R′C═CR′CR′₂CR′₂, R′₂CSiR′₂, R′₂SiSiR′₂, R′₂SiOSiR′₂, R′₂CSiR′₂CR′₂,R′₂SiCR′₂SiR′₂, R′C═CR′SiR′₂, R′₂CGeR′₂, R′₂GeGeR′₂, R′₂CGeR′₂CR′₂,R′₂GeCR′₂GeR′₂, R′₂SiGeR′₂, R′C═CR′GeR′₂, R′B, R′₂C—BR′, R′₂C—BR′—CR′₂,R′₂C—O—CR′₂, R′₂CR′₂C—O—CR′₂CR′₂, R′₂C—O—CR′₂CR′₂, R′₂C—O—CR′═CR′,R′₂C—S—CR′₂, R′₂CR′₂C—S—CR′₂CR′₂, R′₂C—S—CR′₂CR′₂, R′₂C—S—CR′═CR′,R′₂C—Se—CR′₂, R′₂CR′₂C—Se—CR′₂CR′₂, R′₂C—Se—CR′₂CR′₂, R′₂C—Se—CR′═CR′,R′₂C—N═CR′, R′₂C—NR′—CR′₂, R′₂C—NR′—CR′₂CR′₂, R′₂C—NR′—CR′═CR′,R′₂CR′₂C—NR′—CR′₂CR′₂, R′₂C—P═CR′, R′₂C—PR′—CR′₂, O, S, Se, Te, NR′,PR′, AsR′, SbR′, O—O, S—S, R′N—NR′, R′N—NR, PR′, O—S, O—NR′, O—PR′,S—NR′, S—PR′, and R′N—PR′ where R′ is hydrogen or a C₁-C₂₀ containinghydrocarbyl, substituted hydrocarbyl, halocarbyl, substitutedhalocarbyl, silylcarbyl or germylcarbyl substituent and optionally twoor more adjacent R′ may join to form a substituted or unsubstituted,saturated, partially unsaturated or aromatic, cyclic or polycyclicsubstituent. Preferred examples for the bridging group T include CH₂,CH₂CH₂, SiMe₂, SiPh₂, SiMePh, Si(CH₂)₃, Si(CH₂)₄, O, S, NPh, PPh, NMe,PMe, NEt, NPr, NBu, PEt, PPr, Me₂SiOSiMe₂, and PBu.

In a preferred embodiment of the invention in any embodiment of anyformula described herein, T is represented by the formula R^(a) ₂J or(R^(a) ₂J)₂, where J is C, Si, or Ge, and each R^(a) is, independently,hydrogen, halogen, C₁ to C₂₀ hydrocarbyl (such as methyl, ethyl, propyl,butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, or dodecyl)or a C₁ to C₂₀ substituted hydrocarbyl, and two R^(a) can form a cyclicstructure including aromatic, partially saturated, or saturated cyclicor fused ring system. Preferably, T is a bridging group comprisingcarbon or silica, such as dialkylsilyl, preferably T is selected fromCH₂, CH₂CH₂, C(CH₃)₂, SiMe₂, SiPh₂, SiMePh, silylcyclobutyl (Si(CH₂)₃),(Ph)₂C, (p-(Et)₃SiPh)₂C, Me₂SiOSiMe₂, and cyclopentasilylene (Si(CH₂)₄).

In a preferred embodiment of the invention, M⁶ is Zr.

In a preferred embodiment of the invention, G is an alkyl amido group,preferably t-butyl amido or do-decyl amido.

In a preferred embodiment of the invention, each X⁵ is, independently,selected from the group consisting of hydrocarbyl radicals having from 1to 20 carbon atoms, aryls, hydrides, amides, alkoxides, sulfides,phosphides, halides, dienes, amines, phosphines, ethers, and acombination thereof (two X⁵'s may form a part of a fused ring or a ringsystem), preferably each X⁵ is independently selected from halides,aryls and C₁ to C₅ alkyl groups, preferably each X⁵ is a phenyl, methyl,ethyl, propyl, butyl, pentyl, bromo, or chloro group. Preferably, eachX⁵ is, independently, a halide, a hydride, an alkyl group, an alkenylgroup or an arylalkyl group.

In an embodiment, each Cp is independently an indene, which may besubstituted or unsubstituted, each M⁶ is zirconium, and each X⁵ is,independently, a halide, a hydride, an alkyl group, an alkenyl group oran arylalkyl group. In any of the embodiments described herein, y may be1, m may be one, n may be 1, J may be N, and R* may be methyl, ethyl,propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, cyclooctyl,cyclododecyl, decyl, undecyl, dodecyl, adamantyl or an isomer thereof.

In yet another embodiment, the one or more second metallocenepolymerization catalysts may comprise one or more metallocene catalystsof: bis(tetrahydroindenyl)Hf Me₂; (dimethylsilyl)₂O bis(indenyl)ZrCl₂;dimethylsilylbis(tetrahydroindenyl)ZrCl₂;dimethylsilyl-(3-phenyl-indenyl)(tetramethylcyclopentadienyl)ZrCl₂;tetramethyldisilylene bis(4-(3,5-di-tert-butylphenyl)-indenyl)ZrCl₂;bis(indenyl)zirconium dichloride; bis(indenyl)zirconium dimethyl;bis(tetrahydro-1-indenyl)zirconium dichloride;bis(tetrahydro-1-indenyl)zirconium dimethyl;dimethylsilylbis(tetrahydroindenyl)zirconium dichloride;dimethylsilylbis(tetrahydroindenyl)zirconium dimethyl;dimethylsilylbis(indenyl)zirconium dichloride; ordimethylsilyl(bisindenyl)zirconium dimethyl.

In another class of embodiments, the second metallocene catalysts maycomprise bis(indenyl)zirconium dichloride, bis(indenyl)zirconiumdimethyl, bis(tetrahydro-1-indenyl)zirconium dichloride,bis(tetrahydro-1-indenyl)zirconium dimethyl,rac/meso-bis(1-ethylindenyl)zirconium dichloride,rac/meso-bis(1-ethylindenyl)zirconium dimethyl,rac/meso-bis(1-methylindenyl)zirconium dichloride,rac/meso-bis(1-methylindenyl)zirconium dimethyl,rac/meso-bis(1-propylindenyl)zirconium dichloride,rac/meso-bis(1-propylindenyl)zirconium dimethyl,rac/meso-bis(1-butylindenyl)zirconium dichloride,rac/meso-bis(1-butylindenyl)zirconium dimethyl, meso-bis(1ethylindenyl)zirconium dichloride, meso-bis(1-ethylindenyl) zirconium dimethyl,(1-methylindenyl)(pentamethyl cyclopentadienyl) zirconium dichloride,(1-methylindenyl)(pentamethyl cyclopentadienyl) zirconium dimethyl, orcombinations thereof.

In yet another class of embodiments, the one or more metallocenecatalyst may comprise rac/meso-bis(1-ethylindenyl)zirconium dichloride,rac/meso-bis(1-ethylindenyl)zirconium dimethyl,rac/meso-bis(1-methylindenyl)zirconium dichloride,rac/meso-bis(1-methylindenyl)zirconium dimethyl,rac/meso-bis(1-propylindenyl)zirconium dichloride,rac/meso-bis(1-propylindenyl)zirconium dimethyl,rac/meso-bis(1-butylindenyl)zirconium dichloride,rac/meso-bis(1-butylindenyl)zirconium dimethyl, meso-bis(1-ethylindenyl)zirconium dichloride, meso-bis(1ethylindenyl) zirconium dimethyl,(1-methylindenyl)(pentamethyl cyclopentadienyl) zirconium dichloride,(1-methylindenyl)(pentamethyl cyclopentadienyl) zirconium dimethyl, orcombinations thereof.

Mixed Catalyst Systems

Two or more of the metallocene catalysts as described herein (preferablyat least one catalyst compound represented by formula (A1) and/or (A2)and at least one catalyst compound represented by formula (B)) may beused in a mixed catalyst system also known as a dual catalyst systemcomprising, for example, two or three metallocene catalysts or any ofthe catalysts described herein or known in the art to be useful forolefin polymerization. They are preferably co-supported, that isdisposed on the same support material, optionally and in addition to,injected into the reactor(s) separately (with or without a support) orin different combinations and proportions together to “trim” or adjustthe polymer product properties according to its target specification.This approach is very useful in controlling polymer product propertiesand insuring uniformity in high volume production of polyolefinpolymers.

For example, catalyst combinations such as bis(1-ethyl-indenyl)zirconium dimethyl and bis(n-propyl-cyclopentadienyl) hafnium dimethyl,may be used in a catalyst system or a mixed catalyst system, sometimesalso referred to as a dual catalyst system if only two catalysts areused. Particularly preferred catalyst systems comprisebis(1-ethyl-indenyl) zirconium dimethyl, bis(n-propyl-cyclopentadienyl)hafnium dimethyl, a support such as silica, and an activator such as analumoxane (i.e., methylalumoxane).

The two transition metal compounds may be used in any ratio. Preferredmolar ratios of all compounds represented by the formula (A) to allcompounds represented by the formula (B) fall within the range of (A:B)1:1000 to 1000:1, alternatively 1:100 to 500:1, alternatively 1:10 to200:1, alternatively 1:1 to 100:1, and alternatively 1:1 to 75:1, andalternatively 5:1 to 50:1. The particular ratio chosen will depend onthe exact catalysts chosen, the method of activation, and the endproduct desired. In a particular embodiment, when using the twocatalysts, where both are activated with the same activator, useful molepercents, based upon the molecular weight of the pre-catalysts, are 10to 99.9% A to 0.1 to 90% B, alternatively 25 to 99% A to 0.5 to 50% B,alternatively 50 to 99% A to 1 to 25% B, and alternatively 75 to 99% Ato 1 to 10% B.

Activators

The catalyst compositions may be combined with activators in any mannerin the art including by supporting them for use in slurry or gas phasepolymerization. Activators are generally compounds that can activate anyone of the catalyst compounds described above by converting the neutralmetal compound to a catalytically active metal compound cation.Non-limiting activators, for example, include alumoxanes, aluminumalkyls, ionizing activators, which may be neutral or ionic, andconventional-type cocatalysts. Preferred activators typically includealumoxane compounds, modified alumoxane compounds, and ionizing anionprecursor compounds that abstract a reactive, σ-bound, metal ligandmaking the metal compound cationic and providing a charge-balancingnon-coordinating or weakly coordinating anion.

Alumoxane Activators

Alumoxane activators are utilized as activators in the catalystcompositions described herein. Alumoxanes are generally oligomericcompounds containing —Al(R¹)—O— sub-units, where R¹ is an alkyl group.Examples of alumoxanes include methylalumoxane (MAO), modifiedmethylalumoxane (MMAO), ethylalumoxane and isobutylalumoxane.Alkylalumoxanes and modified alkylalumoxanes are suitable as catalystactivators, particularly when the abstractable ligand is an alkyl,halide, alkoxide or amide. Mixtures of different alumoxanes and modifiedalumoxanes may also be used. It may be preferable to use a visuallyclear methylalumoxane. A cloudy or gelled alumoxane can be filtered toproduce a clear solution or clear alumoxane can be decanted from thecloudy solution. A useful alumoxane is a modified methyl alumoxane(MMAO) cocatalyst type 3A (commercially available from Akzo Chemicals,Inc. under the trade name Modified Methylalumoxane type 3A, coveredunder patent number U.S. Pat. No. 5,041,584).

When the activator is an alumoxane (modified or unmodified), someembodiments select the maximum amount of activator typically at up to a5000-fold molar excess Al/M over the catalyst compound (per metalcatalytic site). The minimum activator-to-catalyst-compound is a 1:1molar ratio. Alternate preferred ranges include from 1:1 to 500:1,alternately from 1:1 to 200:1, alternately from 1:1 to 100:1, oralternately from 1:1 to 50:1.

In a class of embodiments, little or no (zero %) alumoxane is used inthe polymerization processes described herein. Alternatively, thealumoxane is present at a molar ratio of aluminum to catalyst compoundtransition metal less than 500:1, preferably less than 300:1, preferablyless than 100:1, and preferably less than 1:1.

In another class of embodiments, the at least one activator comprisesaluminum and the aluminum to transition metal, for example, hafnium orzirconium, ratio is at least 150 to 1; the at least one activatorcomprises aluminum and the aluminum to transition metal, for example,hafnium or zirconium, ratio is at least 250 to 1; or the at least oneactivator comprises aluminum and the aluminum to transition metal, forexample, hafnium or zirconium, ratio is at least 1,000 to 1.

Ionizing/Non Coordinating Anion Activators

The term “non-coordinating anion” (NCA) means an anion which either doesnot coordinate to a cation or which is only weakly coordinated to acation thereby remaining sufficiently labile to be displaced by aneutral Lewis base. “Compatible” non-coordinating anions are those whichare not degraded to neutrality when the initially formed complexdecomposes. Further, the anion will not transfer an anionic substituentor fragment to the cation so as to cause it to form a neutral transitionmetal compound and a neutral by-product from the anion. Non-coordinatinganions useful in accordance with this invention are those that arecompatible, stabilize the transition metal cation in the sense ofbalancing its ionic charge at +1, and yet retain sufficient lability topermit displacement during polymerization. Ionizing activators usefulherein typically comprise an NCA, particularly a compatible NCA.

It is within the scope of this invention to use an ionizing activator,neutral or ionic, such as tri (n-butyl) ammonium tetrakis(pentafluorophenyl) borate, a tris perfluorophenyl boron metalloidprecursor or a tris perfluoronaphthyl boron metalloid precursor,polyhalogenated heteroborane anions (WO 98/43983), boric acid (U.S. Pat.No. 5,942,459), or combination thereof. It is also within the scope ofthis invention to use neutral or ionic activators alone or incombination with alumoxane or modified alumoxane activators.

For descriptions of useful activators please see U.S. Pat. Nos.8,658,556 and 6,211,105.

Preferred activators include N,N-dimethylaniliniumtetrakis(perfluoronaphthyl)borate, N,N-dimethylaniliniumtetrakis(perfluorobiphenyl)borate, N,N-dimethylaniliniumtetrakis(perfluorophenyl)borate, N,N-dimethylaniliniumtetrakis(3,5-bis(trifluoromethyl)phenyl)borate, triphenylcarbeniumtetrakis(perfluoronaphthyl)borate, triphenylcarbeniumtetrakis(perfluorobiphenyl)borate, triphenylcarbeniumtetrakis(3,5-bis(trifluoromethyl)phenyl)borate, triphenylcarbeniumtetrakis(perfluorophenyl)borate, trimethylammoniumtetrakis(perfluorophenyl)borate;1-(4-(tris(pentafluorophenyl)borate)-2,3,5,6-tetrafluorophenyl)pyrrolidinium;and tetrakis(pentafluorophenyl)borate,4-(tris(pentafluorophenyl)borate)-2,3,5,6-tetrafluoropyridine.

In a preferred embodiment, the activator comprises a triaryl carbonium(such as triphenylcarbenium tetraphenylborate, triphenylcarbeniumtetrakis(pentafluorophenyl)borate, triphenylcarbeniumtetrakis-(2,3,4,6-tetrafluorophenyl)borate, triphenylcarbeniumtetrakis(perfluoronaphthyl)borate, triphenylcarbeniumtetrakis(perfluorobiphenyl)borate, triphenylcarbeniumtetrakis(3,5-bis(trifluoromethyl)phenyl)borate).

In another embodiment, the activator comprises one or more oftrialkylammonium tetrakis(pentafluorophenyl)borate, N,N-dialkylaniliniumtetrakis(pentafluorophenyl)borate,N,N-dimethyl-(2,4,6-trimethylanilinium)tetrakis(pentafluorophenyl)borate, trialkylammoniumtetrakis-(2,3,4,6-tetrafluorophenyl) borate, N,N-dialkylaniliniumtetrakis-(2,3,4,6-tetrafluorophenyl)borate, trialkylammoniumtetrakis(perfluoronaphthyl)borate, N,N-dialkylaniliniumtetrakis(perfluoronaphthyl)borate, trialkylammoniumtetrakis(perfluorobiphenyl)borate, N,N-dialkylaniliniumtetrakis(perfluorobiphenyl)borate, trialkylammoniumtetrakis(3,5-bis(trifluoromethyl)phenyl)borate, N,N-dialkylaniliniumtetrakis(3,5-bis(trifluoromethyl)phenyl)borate,N,N-dialkyl-(2,4,6-trimethylanilinium)tetrakis(3,5-bis(trifluoromethyl)phenyl)borate, di-(i-propyl)ammoniumtetrakis(pentafluorophenyl)borate, (where alkyl is methyl, ethyl,propyl, n-butyl, sec-butyl, or t-butyl).

The typical activator-to-catalyst ratio, e.g., all NCAactivators-to-catalyst ratio is about a 1:1 molar ratio. Alternatepreferred ranges include from 0.1:1 to 100:1, alternately from 0.5:1 to200:1, alternately from 1:1 to 500:1 alternately from 1:1 to 1000:1. Aparticularly useful range is from 0.5:1 to 10:1, preferably 1:1 to 5:1.

Support Materials

The catalyst composition comprises at least one “support” or sometimesalso referred to as a “carrier”. The terms may be interchangeable unlessotherwise distinguished. Suitable supports, include but are not limitedto silica, alumina, silica-alumina, zirconia, titania, silica-alumina,cerium oxide, magnesium oxide, or combinations thereof. The catalyst mayoptionally comprise a support or be disposed on at least one support.Suitable supports, include but are not limited to, active and inactivematerials, synthetic or naturally occurring zeolites, as well asinorganic materials such as clays and/or oxides such as silica, alumina,zirconia, titania, silica-alumina, cerium oxide, magnesium oxide, orcombinations thereof. In particular, the support may be silica-alumina,alumina and/or a zeolite, particularly alumina. Silica-alumina may beeither naturally occurring or in the form of gelatinous precipitates orgels including mixtures of silica and metal oxides.

In class of embodiments, the at least one support may comprise anorganosilica material. The organosilica material supports may be apolymer formed of at least one monomer. In certain embodiments, theorganosilica material may be a polymer formed of multiple distinctmonomers. Methods and materials for producing the organosilica materialsas well as a characterization description may be found in, for example,WO 2016/094770 and WO 2016 094774.

Preferably, the support material is an inorganic oxide in a finelydivided form. Suitable inorganic oxide materials for use in catalystsystems herein include Groups 2, 4, 13, and 14 metal oxides, such assilica, alumina, and mixtures thereof. Other inorganic oxides that maybe employed either alone or in combination with the silica, or aluminaare magnesia, titania, zirconia, and the like. Other suitable supportmaterials, however, can be employed, for example, finely dividedfunctionalized polyolefins, such as finely divided polyethylene.Particularly useful supports include magnesia, titania, zirconia,montmorillonite, phyllosilicate, zeolites, talc, clays, and the like.Also, combinations of these support materials may be used, for example,silica-chromium, silica-alumina, silica-titania, and the like. Preferredsupport materials include Al₂O₃, ZrO₂, SiO₂, and combinations thereof,more preferably SiO₂, Al₂O₃, or SiO₂/Al₂O₃.

Scavengers, Chain Transfer Agents and/or Co-Activators

Scavengers, chain transfer agents, or co-activators may also be used.Aluminum alkyl compounds which may be utilized as scavengers orco-activators include, for example, one or more of those represented bythe formula AlR₃, where each R is, independently, a C₁-C₈ aliphaticradical, preferably methyl, ethyl, propyl, butyl, pentyl, hexyl octyl oran isomer thereof), especially trimethylaluminum, triethylaluminum,triisobutylaluminum, tri-n-hexylaluminum, tri-n-octylaluminum ormixtures thereof.

Useful chain transfer agents that may also be used herein are typicallya compound represented by the formula AlR²⁰ ₃, ZnR²⁰ ₂ (where each R²⁰is, independently, a C₁-C₈ aliphatic radical, preferably methyl, ethyl,propyl, butyl, pentyl, hexyl octyl or an isomer thereof) or acombination thereof, such as diethyl zinc, trimethylaluminum,triisobutylaluminum, trioctylaluminum, or a combination thereof.

Catalyst Component Solution (the “Trim Solution”)

The catalyst component solution may include only catalyst compound(s),such as a metallocene, or may include an activator. In at least oneembodiment, the catalyst compound(s) in the catalyst component solutionis unsupported. The catalyst solution used in the trim process can beprepared by dissolving the catalyst compound and optional activators ina liquid solvent. The liquid solvent may be an alkane, such as a C₅ toC₃₀ alkane, or a C₅ to C₁₀ alkane. Cyclic alkanes such as cyclohexaneand aromatic compounds such as toluene may also be used. Mineral oil maybe used as a solvent alternatively or in addition to other alkanes suchas a C₅ to C₃₀ alkane. Mineral oil can have a density of from 0.85 g/cm³to 0.9 g/cm³ at 25° C. according to ASTM D4052, such as from 0.86 g/cm³to 0.88 g/cm³. Mineral oil can have a kinematic viscosity @ 25° C. offrom 150 cSt to 200 cSt according to ASTM D341, such as from 160 cSt to190 cSt, such as about 170 cSt. Mineral oil can have an averagemolecular weight of from 400 g/mol to 600 g/mol according to ASTM D2502,such as from 450 g/mol to 550 g/mol, such as about 500 g/mol. In atleast one embodiment, a mineral oil is HYDROBRITE® 380 PO White MineralOil (“HB380”) from Sonneborn, LLC.

The solution employed should be liquid under the conditions ofpolymerization and relatively inert. In one embodiment, the liquidutilized in the catalyst compound solution is different from the diluentused in the catalyst component slurry. In another embodiment, the liquidutilized in the catalyst compound solution is the same as the diluentused in the catalyst component solution.

If the catalyst solution includes both activator and catalyst compound,the ratio of metal in the activator to metal in the catalyst compound inthe solution may be 1000:1 to 0.5:1, 300:1 to 1:1, or 150:1 to 1:1. Invarious embodiments, the activator and catalyst compound are present inthe solution at up to about 90 wt %, at up to about 50 wt %, at up toabout 20 wt %, preferably at up to about 10 wt %, at up to about 5 wt %,at less than 1 wt %, or between 100 ppm and 1 wt %, based upon theweight of the solvent and the activator or catalyst compound.

The catalyst component solution can include any one of the catalystcompound(s) of the present disclosure. As the catalyst is dissolved inthe solution, a higher solubility is desirable. Accordingly, thecatalyst compound in the catalyst component solution may often include ametallocene, which may have higher solubility than other catalysts.

In the polymerization process, described below, any of the abovedescribed catalyst component containing solutions may be combined withany of the catalyst component containing slurry/slurries describedabove. In addition, more than one catalyst component solution may beutilized.

Continuity Additive/Static Control Agent

In gas-phase polyethylene production processes, it may be desirable touse one or more continuity additives to aid in reactor operability.While not wishing to be bound by any particular theory, static controlagents to aid in regulating static levels in the reactor. As usedherein, a static control agent is a chemical composition which, whenintroduced into a fluidized bed reactor, may influence or drive thestatic charge (negatively, positively, or to zero) in the fluidized bed.The specific static control agent used may depend upon the nature of thestatic charge, and the choice of static control agent may vary dependentupon the polymer being produced and the single site catalyst compoundsbeing used.

Control agents such as aluminum stearate may be employed. The staticcontrol agent used may be selected for its ability to receive the staticcharge in the fluidized bed without adversely affecting productivity.Other suitable static control agents may also include aluminumdistearate, ethoxylated amines, and anti-static compositions such asthose provided by Innospec Inc. under the trade name OCTASTAT. Forexample, OCTASTAT 2000 is a mixture of a polysulfone copolymer, apolymeric polyamine, and oil soluble sulfonic acid.

Desirable control agents may adversely affect productivity whileimproving reactor operation. A desired concentration of any controlagents used could be determined by optimizing the improvement in reactoroperation with adverse affects in productivity. Typical concentrationranges can vary between 0-100 ppm by weight solids based on reactor bedweight.

Any of the mentioned control agents may be employed either alone or incombination as a control agent. For example, the carboxylate metal saltmay be combined with an amine containing control agent (e.g., acarboxylate metal salt with any family member belonging to theKEMAMINE(R) (available from Crompton Corporation) or ATMER(R) (availablefrom ICI Americas Inc.) family of products).

Other useful continuity additives include ethyleneimine additives usefulin embodiments disclosed herein may include polyethyleneimines havingthe following general formula: —(CH₂—CH₂—NH)n-, where n may be fromabout 10 to about 10,000. The polyethyleneimines may be linear,branched, or hyper branched (e.g., forming dendritic or arborescentpolymer structures). They can be a homopolymer or copolymer ofethyleneimine or mixtures thereof (referred to as polyethyleneimine(s)hereafter). Although linear polymers represented by the chemical formula—(CH₂—CH₂—NH)n- may be used as the polyethyleneimine, materials havingprimary, secondary, and tertiary branches can also be used. Commercialpolyethyleneimine can be a compound having branches of the ethyleneiminepolymer.

Gas Phase Polymerization Reactor

FIG. 2 is a schematic of a gas-phase reactor system 100, showing theaddition of at least two catalysts, at least one of which is added as atrim catalyst. The catalyst component slurry in diluent, such as amineral oil slurry, including at least one support and at least oneactivator, and at least one catalyst compound (such as two differentcatalyst compounds) may be placed in a vessel or catalyst pot (cat pot)102. The slurry diluent can further include a wax, which can provideincreased viscosity to the mineral oil slurry, which provides for use ofa slurry roller of conventional trim processes to be merely optional.Lower viscosity slurries of conventional trim processes involve rollingthe slurry cylinders immediately prior to use. Not using a slurry rollercan provide reduced or eliminated foam when the slurry is transferreddown in pressure to the slurry vessel (e.g., cat pot 102). In someembodiments, the viscosity of a mineral oil slurry comprising a wax issuch that the time scale of settling of suspended solids in the slurryis longer than the time scale of use of the slurry in a polymerizationprocess. As such, agitation of the slurry (e.g., cat pot 102) can belimited or unnecessary.

Paraffin waxes can include SONO JELL® paraffin waxes, such as SONO JELL®4 and SONO JELL® 9 from Sonneborn, LLC. SONO JELL® paraffin waxes arecompositions that typically contain 10 wt % or more of wax and up to 90wt % of mineral oil. For example, a SONO JELL® paraffin wax can be 20 wt% wax and 80 wt % mineral oil. In at least one embodiment, a mineral oilslurry has 5 wt % or greater of wax, such as 10 wt % or greater, such as25 wt % or greater, such as 40 wt % or greater, such as 50 wt % orgreater, such as 60 wt % or greater, such as 70 wt % or greater. Forexample, a mineral oil slurry can have 70 wt % mineral oil, 10 wt % wax,and 20 wt % supported dual catalyst. It has been discovered that theincreased viscosity provided by including a wax in the mineral oilslurry provides reduced settling of supported dual catalyst in a vesselor catalyst pot. It has further been discovered that using an increasedviscosity mineral oil slurry does not inhibit trim efficiency.

Cat pot 102 is an agitated holding tank designed to keep the solidsconcentration homogenous. In at least one embodiment, cat pot 102 ismaintained at an elevated temperature, such as from 30° C. to 75° C.,such as from 40° C. to 45° C., for example about 43° C. or about 60° C.Elevated temperature can be obtained by electrically heat tracing catpot 102 using, for example, a heating blanket. Cat pot 102 that ismaintained at an elevated temperature can provide a wax-containingmineral oil slurry that has slurry stability for 6 days or more, e.g. asettling rate of supported catalyst of 40% or less after 6 days.Furthermore, it has been discovered that maintaining cat pot 102 at anelevated temperature can also reduce or eliminates foaming, inparticular when a wax is present in the mineral oil slurry. Withoutbeing bound by theory, a synergy provided by increased viscosity of theslurry provided by the wax and decreased viscosity provided by elevatedtemperature of the slurry can provide the reduced or eliminated foamformation in a cat pot vessel. Maintaining cat pot 102 at an elevatedtemperature can further reduce or eliminate solid residue formation onvessel walls which could otherwise slide off of the walls and causeplugging in downstream delivery lines. In at least one embodiment, catpot 102 has a volume of from about 300 gallons to 2,000 gallons, such asfrom 400 gallons to 1,500 gallons, such as from 500 gallons to 1,000gallons, such as from 500 gallons to 800 gallons, for example about 500gallons.

In at least one embodiment, cat pot 102 is also maintained at pressureof 25 psig or greater, such as from 25 psig to 75 psig, such as from 30psig to 60 psig, for example about 50 psig. Conventional trim processesinvolve slurry cylinders rolled at 25 psig, and foam is created whentransferred down in pressure to the slurry vessel. It has beendiscovered that operating a slurry vessel (e.g., cat pot 102) at higherpressures can reduce or prevent foam.

In at least one embodiment, piping 130 and piping 140 of gas-phasereactor system 100 is maintained at an elevated temperature, such asfrom 30° C. to 75° C., such as from 40° C. to 45° C., for example about43° C. or about 60° C. Elevated temperature can be obtained byelectrically heat tracing piping 130 and or piping 140 using, forexample, a heating blanket. Maintaining piping 130 and or piping 140 atan elevated temperature can provide the same or similar benefits asdescribed for an elevated temperature of cat pot 102.

A catalyst component solution, prepared by mixing a solvent and at leastone catalyst compound and/or activator, is placed in another vessel,such as a trim pot 104. Trim pot 104 can have a volume of from about 100gallons to 2,000 gallons, such as from 100 gallons to 1,500 gallons,such as from 200 gallons to 1,000 gallons, such as from 200 gallons to500 gallons, for example about 300 gallons. Trim pot 104 can bemaintained at an elevated temperature, such as from 30° C. to 75° C.,such as from 40° C. to 45° C., for example about 43° C. or about 60° C.Elevated temperature can be obtained by electrically heat tracing trimpot 104 using, for example, a heating blanket. Maintaining trim pot 104at an elevated temperature can provide reduced or eliminated foaming inpiping 130 and or piping 140 when the catalyst component slurry from catpot 102 is combined in-line (also referred to herein as “on-line”) withthe catalyst component solution from trim pot 104.

It has been discovered that if the catalyst component slurry includes awax, then it is advantageous that a diluent of the catalyst componentsolution have a viscosity that is greater than the viscosity of analkane solvent, such as isopentane (iC5) or isohexane (iC6). Using iC5or iC6 as a diluent in a trim pot can promote catalyst settling andstatic mixer plugging. Accordingly, in at least one embodiment, thecatalyst component slurry of cat pot 102 includes a wax, as describedabove, and the catalyst component solution of trim pot 104 includes adiluent that is mineral oil. It has been discovered that trim efficiencyis maintained or improved using wax in the catalyst component slurry andmineral oil in the catalyst component solution. Furthermore, use of waxand mineral oil reduces or eliminates the amount of iC5 and iC6 used ina trim process, which can reduce or eliminate emissions of volatilematerial (such as iC5 and iC6). Mineral oil can have a density of from0.85 g/cm³ to 0.9 g/cm³ at 25° C. according to ASTM D4052, such as from0.86 g/cm³ to 0.88 g/cm³. Mineral oil can have a kinematic viscosity at40° C. of from 70 cSt to 240 cSt according to ASTM D445, such as from160 cSt to 190 cSt, such as about 170 cSt. Mineral oil can have anaverage molecular weight of from 400 g/mol to 600 g/mol according toASTM D2502, such as from 450 g/mol to 550 g/mol, such as about 500g/mol. In at least one embodiment, a mineral oil is HB380 fromSonneborn, LLC or HydroBrite 1000 white mineral oil.

The catalyst component slurry can then be combined in-line with thecatalyst component solution to form a final catalyst composition. Anucleating agent 106, such as silica, alumina, fumed silica or any otherparticulate matter may be added to the slurry and/or the solutionin-line or in the vessels 102 or 104. Similarly, additional activatorsor catalyst compounds may be added in-line. For example, a secondcatalyst slurry (catalyst component solution) that includes a differentcatalyst may be introduced from a second cat pot (which may include waxand mineral oil). The two catalyst slurries may be used as the catalystsystem with or without the addition of a solution catalyst from the trimpot.

The catalyst component slurry and solution can be mixed in-line. Forexample, the solution and slurry may be mixed by utilizing a staticmixer 108 or an agitating vessel. The mixing of the catalyst componentslurry and the catalyst component solution should be long enough toallow the catalyst compound in the catalyst component solution todisperse in the catalyst component slurry such that the catalystcomponent, originally in the solution, migrates to the supportedactivator originally present in the slurry. The combination forms auniform dispersion of catalyst compounds on the supported activatorforming the catalyst composition. The length of time that the slurry andthe solution are contacted is typically up to about 220 minutes, such asabout 1 to about 60 minutes, about 2 to about 20 minutes, or about 3 toabout 10 minutes.

In at least one embodiment, static mixer 108 of gas-phase reactor system100 is maintained at an elevated temperature, such as from 30° C. to 75°C., such as from 40° C. to 45° C., for example about 43° C. or about 60°C. Elevated temperature can be obtained by electrically heat tracingstatic mixer 108 using, for example, a heating blanket. Maintainingstatic mixer 108 at an elevated temperature can provide reduced oreliminated foaming in static mixer 108 and can promote mixing of thecatalyst component slurry and catalyst solution (as compared to lowertemperatures) which reduces run times in the static mixer and for theoverall polymerization process.

When combining the catalysts, the activator and the optional support oradditional co-catalysts in the hydrocarbon solvents immediately prior toa polymerization reactor, the combination can yield a new polymerizationcatalyst in less than 1 h, less than 30 min, or less than 15 min.Shorter times are more effective, as the new catalyst is ready beforebeing introduced into the reactor, which can provide faster flow rates.

In another embodiment, an aluminum alkyl, an ethoxylated aluminum alkyl,an aluminoxane, an anti-static agent or a borate activator, such as a C₁to Cis alkyl aluminum (for example tri-isobutyl aluminum, trimethylaluminum or the like), a C₁ to Cis ethoxylated alkyl aluminum or methylaluminoxane, ethyl aluminoxane, isobutylaluminoxane, modifiedaluminoxane or the like are added to the mixture of the slurry and thesolution in line. The alkyls, antistatic agents, borate activatorsand/or aluminoxanes may be added from an alkyl vessel 110 directly tothe combination of the solution and the slurry, or may be added via anadditional alkane (such as hexane, heptane, and or octane) carrierstream, for example, from a carrier vessel 112. The additional alkyls,antistatic agents, borate activators and/or aluminoxanes may be presentat up to 500 ppm, at 1 to 300 ppm, at 10 ppm to 300 ppm, or at 10 to 100ppm. A carrier gas 114 such as nitrogen, argon, ethane, propane, and thelike, may be added in-line to the mixture of the slurry and thesolution. Typically the carrier gas may be added at the rate of about 1to about 100 lb/hr (0.4 to 45 kg/hr), or about 1 to about 50 lb/hr (5 to23 kg/hr), or about 1 to about 33 lb/hr (0.4 to 15 kg/hr).

A condensing agent can be added directly to the reactor and or piping140 (e.g., the combination of the solution and the slurry), for example,from a condensing agent vessel 180. Condensing agents include C₃-C₇hydrocarbons, such as iC5, nC5, iC4, and nC₄. The condensing agent maybe added introduced into the reactor or the line (e.g., contacted withthe mixture of the slurry and the solution), such that the condensingagent is from 0.1 mol % to 50 mol % of components (e.g., monomers,comonomers, Hz, and condensing agent) in the top (vapor) portion of thereactor, such as from 0.1 mol % to 40 mol %, such as from 1 mol % to 25mol %, such as from 12 mol % to 25 mol %, such as from 8 mol % to 17 mol%, such as from 3 mol % to 18 mol %, such as from 5 mol % to 12 mol %.It has been discovered that providing a controlled amount of condensingagent to a polymerization can control the Mw, MI, HLMI, and MIR of apolymer product without substantially affecting polymer density. Withoutbeing bound by theory, a condensing agent can alter the concentration ofcomonomer present at a catalyst active site during polymerization, thusaffecting comonomer incorporation (and Mw, MI, MWD and MIR), but withoutaffecting the density of the polymer product. In some embodiments, amolar ratio of first catalyst to second catalyst (before or aftertrimming the catalyst system) can be from about 1:99 to 99:1, such asfrom 85:15 to 50:50, such as from 80:20 to 50:50, such as from 70:30 to50:50. The amount of condensing agent can be adjusted during apolymerization, e.g. from 5 mol % to 11.5 mol %, which can adjust one ormore polymer properties. For example, if iC5 is provided to apolymerization at 5.5 mol % to provide polymer with an MIR of 52, theiC5 content can be increased to 11 mol % to provide polymer producthaving an MIR of 65.

In at least one embodiment, a liquid carrier stream is introduced intothe combination of the solution and slurry. The mixture of the solution,the slurry and the liquid carrier stream may pass through a mixer orlength of tube for mixing before being contacted with a gaseous carrierstream. Similarly, a comonomer 116, such as hexene, anotheralpha-olefin, or diolefin, may be added in-line to the mixture of theslurry and the solution.

In one embodiment, a gas stream 126, such as cycle gas, or re-cycle gas124, monomer, nitrogen, or other materials is introduced into aninjection nozzle 300 having a support tube 128 that surrounds aninjection tube 120. The slurry/solution mixture is passed through theinjection tube 120 to a reactor 122. In some embodiments, the injectiontube may aerosolize the slurry/solution mixture. Any number of suitabletubing sizes and configurations may be used to aerosolize and/or injectthe slurry/solution mixture.

FIG. 3 is a schematic diagram of nozzle 300 which can be configured in avariety of ways. As shown in FIG. 3, injection nozzle 300 is in fluidcommunication with one or more feed lines (three are shown in FIG. 3)240A, 242A, 244A. Each feed line 240A, 242A, 244A provides anindependent flow path for one or more monomers, purge gases, catalystand/or catalyst systems to any one or more of the conduits 220 and 240.Feed line 240A or 242A provides the feed provided by piping 140 (shownin FIG. 2), and the remaining feed lines independently provide feedsfrom piping of a similar or same apparatus, such as the trim feedapparatus of FIG. 2. Alternatively, feed lines 240A, 242A, and 244Aindependently provide catalyst slurry, catalyst component solution,liquid carrier stream, monomer, or comonomer. The first conduit 240 mayeither protrude farther into the reactor than the second conduit 220 orbe slightly recessed depending on the desired configuration. The firstconduit 240 may be conventional tubing or it may have openings allowingflow into the annulus outside first conduit 240 and inside the secondconduit 220.

Any of the one or more catalyst or catalyst systems, purge gases,condensing agents and monomers can be injected into any of the one ormore feed lines 240A, 242A, 244A. The one or more catalyst or catalystsystems can be injected into the first conduit 240 using the first feedline 240A. Purge or inert gases and/or condensing agent may also bepresent in the first feed line 240A. The one or more purge gases orinert gases and condensing agent can be injected into the second conduit220 using the second feed line 242A. The one or more monomers or aslipstream of “cycle gas” with the same composition as line 124 in FIG.2 can be injected into the support member 128 using the third feed line244A. The feed lines 240A, 242A, 244A can be any conduit capable oftransporting a fluid therein. Suitable conduits can include tubing, flexhose, and pipe. A condensing agent can be injected into first conduit240, second conduit 220, and/or support member 128 via respective feedlines 240A, 242A, and/or 244A, alone or in combination with the othercomponents moving through the conduits, support member, and/or feedlines. A three way valve 215 can be used to introduce and control theflow of the fluids (i.e. catalyst slurry, purge gas and monomer) to theinjection nozzle 300. Any suitable commercially available three wayvalve can be used.

In at least one embodiment, a nozzle is a conventional “slurry” nozzlehaving a first conduit that is conventional tubing and typicallyprotrudes farther into the reactor than a second conduit. The precedingparagraph describes acceptable configurations.

In at least one embodiment, nozzle 300 is an “effervescent” nozzle. Ithas been discovered that use of an effervescent nozzle can provide a3-fold increase or more in nozzle efficiency of a trim process ascompared to conventional slurry nozzles. A suitable effervescent nozzlefor at least one embodiment of the present disclosure is shown in U.S.Patent Pub. No. 2010/0041841 A1.

Support member 128 can include a first end having a flanged section 252.The support member 128 can also include a second end that is open toallow a fluid to flow there through. In one or more embodiments, supportmember 128 is secured to a reactor wall 210. In one or more embodiments,flanged section 252 can be adapted to mate or abut up against a flangedportion 205 of the reactor wall 210 as shown.

The flow through support tube 128 can be from 50 kg/hr to 1,150 kg/hr,such as from 100 kg/hr to 950 kg/hr, such as from 100 kg/hr to 500kg/hr, such as from 100 kg/hr to 300 kg/hr, such as from 180 kg/hr to270 kg/hr, such as from 150 kg/hr to 250 kg/hr, for example about 180kg/hr. These flow rates can be achieved by a support tube, such assupport tube 128, having a diameter of from ¼ inch to ¾ inch, forexample about ½ inch. A diameter of from ¼ inch to ¾ inch has beendiscovered to provide reduced flow rates as compared to conventionaltrim process flow rates (e.g., 1,200 kg/hr), which further providesreduced overall amounts of liquid carrier (such as iC5) and nitrogenused during a polymerization process.

In at least one embodiment, a carrier gas flow rate is from 1 kg/hr to50 kg/hr, such as from 1 kg/hr to 25 kg/hr, such as from 2 kg/hr to 20kg/hr, such as from 2.5 kg/hr to 15 kg/hr. In at least one embodiment, acarrier fluid flow rate is from 1 kg/hr to 100 kg/hr, such as from 2kg/hr to 50 kg/hr, such as from 2 kg/hr to 30 kg/hr, such as from 3kg/hr to 25 kg/hr, for example about 15 kg/hr.

Returning to FIG. 2, to promote formation of particles in the reactor122, a nucleating agent 118, such as fumed silica, can be added directlyinto the reactor 122. Conventional trim polymerization processes involvea nucleating agent introduced into a polymerization reactor. However,processes of the present disclosure have provided advantages such thataddition of a nucleating agent (such as spray dried fumed silica) to thereactor is merely optional. For embodiments of processes of the presentdisclosure that do not include a nucleating agent, it has beendiscovered that a high polymer bulk density (e.g., 0.4 g/cm³ or greater)can be obtained, which is greater than the bulk density of polymersformed by conventional trim processes. Furthermore, when a metallocenecatalyst or other similar catalyst is used in the gas phase reactor,oxygen or fluorobenzene can be added to the reactor 122 directly or tothe gas stream 126 to control the polymerization rate. Thus, when ametallocene catalyst (which is sensitive to oxygen or fluorobenzene) isused in combination with another catalyst (that is not sensitive tooxygen) in a gas phase reactor, oxygen can be used to modify themetallocene polymerization rate relative to the polymerization rate ofthe other catalyst. An example of such a catalyst combination isbis(n-propylcyclopentadienyl) zirconium dichloride and[(2,4,6-Me₃C₆H₂)NCH₂CH₂)]₂NHZrBn₂, where Me is methyl orbis(indenyl)zirconium dichloride and [(2,4,6-Me₃C₆H₂)NCH₂CH₂)]₂NHHfBn₂,where Me is methyl. For example, if the oxygen concentration in thenitrogen feed is altered from 0.1 ppm to 0.5 ppm, significantly lesspolymer from the bisindenyl ZrCl₂ will be produced and the relativeamount of polymer produced from the [(2,4,6-Me₃C₆H₂)NCH₂CH₂)]₂NHHfBn₂ isincreased. WO 1996/009328 discloses the addition of water or carbondioxide to gas phase polymerization reactors, for example, for similarpurposes.

The example above is not limiting, as additional solutions and slurriesmay be included. For example, a slurry can be combined with two or moresolutions having the same or different catalyst compounds and oractivators. Likewise, the solution may be combined with two or moreslurries each having the same or different supports, and the same ordifferent catalyst compounds and or activators. Similarly, two or moreslurries combined with two or more solutions, preferably in-line, wherethe slurries each comprise the same or different supports and maycomprise the same or different catalyst compounds and or activators andthe solutions comprise the same or different catalyst compounds and oractivators. For example, the slurry may contain a supported activatorand two different catalyst compounds, and two solutions, each containingone of the catalysts in the slurry, and each are independently combined,in-line, with the slurry.

Use of Catalyst Composition to Control Product Properties

The properties of the product polymer may be controlled by adjusting thetiming, temperature, concentrations, and sequence of the mixing of thesolution, the slurry and any optional added materials (condensing agent,nucleating agents, catalyst compounds, activators, etc.) describedabove. The MWD, MI, density, MIR, relative amount of polymer produced byeach catalyst, and other properties of the polymer produced may also bechanged by manipulating process parameters. Any number of processparameters may be adjusted, including manipulating hydrogenconcentration in the polymerization system, changing the amount of thefirst catalyst in the polymerization system, or changing the amount ofthe second catalyst in the polymerization system. Other processparameters that can be adjusted include changing the relative ratio ofthe catalyst in the polymerization process (and optionally adjustingtheir individual feed rates to maintain a steady or constant polymerproduction rate). The concentrations of reactants in the reactor 122 canbe adjusted by changing the amount of liquid or gas that is withdrawn orpurged from the process, changing the amount and/or composition of arecovered liquid and/or recovered gas returned to the polymerizationprocess, wherein the recovered liquid or recovered gas can be recoveredfrom polymer discharged from the polymerization process. Further processparameters including concentration parameters that can be adjustedinclude changing the polymerization temperature, changing the ethylenepartial pressure in the polymerization process, changing the ethylene tocomonomer ratio in the polymerization process, changing the activator totransition metal ratio in the activation sequence. Time dependentparameters may be adjusted such as changing the relative feed rates ofthe slurry or solution, changing the mixing time, the temperature and ordegree of mixing of the slurry and the solution in-line, addingdifferent types of activator compounds to the polymerization process,and adding oxygen or fluorobenzene or other catalyst poison to thepolymerization process. Any combinations of these adjustments may beused to control the properties of the final polymer product.

In one embodiment, the MWD of the polymer product is measured at regularintervals and one of the above process parameters, such as temperature,catalyst compound feed rate, the ratios of the two or more catalysts toeach other, the ratio of comonomer to monomer, the monomer partialpressure, and or hydrogen concentration, is altered to bring thecomposition to the desired level, if necessary. The MWD may be measuredby size exclusion chromatography (SEC), e.g., gel permeationchromatography (GPC), among other techniques.

In one embodiment, a polymer product property is measured in-line and inresponse the ratio of the catalysts being combined is altered. In oneembodiment, the molar ratio of the catalyst compound in the catalystcomponent slurry to the catalyst compound in the catalyst componentsolution, after the slurry and solution have been mixed to form thefinal catalyst composition, is 500:1 to 1:500, or 100:1 to 1:100, or50:1 to 1:50 or 40:1 to 1:10. In another embodiment, the molar ratio ofa Group 15 catalyst compound in the slurry to a metallocene catalystcompound in the solution, after the slurry and solution have been mixedto form the catalyst composition, is 500:1, 100:1, 50:1, 10:1, or 5:1.The product property measured can include the dynamic shear viscosity,flow index, melt index, density, MWD, comonomer content, andcombinations thereof. In another embodiment, when the ratio of thecatalyst compounds is altered, the introduction rate of the catalystcomposition to the reactor, or other process parameters, is altered tomaintain a desired production rate.

Polymerization Process

The catalyst system can be used to polymerize one or more olefins toprovide one or more polymer products therefrom. Any suitablepolymerization process can be used, including, but not limited to, highpressure, solution, slurry, and/or gas phase polymerization processes.In embodiments that use other techniques besides gas phasepolymerization, modifications to a catalyst addition system that aresimilar to those discussed with respect to FIG. 2 and or FIG. 3 can beused. For example, a trim system may be used to feed catalyst to a loopslurry reactor for polyethylene copolymer production.

The terms “polyethylene” and “polyethylene copolymer” refer to a polymerhaving at least 50 wt % ethylene derived units. In various embodiments,the polyethylene can have at least 70 wt % ethylene-derived units, atleast 80 wt % ethylene-derived units, at least 90 wt % ethylene-derivedunits, or at least 95 wt % ethylene-derived units. The polyethylenepolymers described herein are generally copolymer, but may also includeterpolymers, having one or more other monomeric units. As describedherein, a polyethylene can include, for example, at least one or moreother olefins or comonomers. Suitable comonomers can contain 3 to 16carbon atoms, from 3 to 12 carbon atoms, from 4 to 10 carbon atoms, andfrom 4 to 8 carbon atoms. Examples of comonomers include, but are notlimited to, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene,1-octene, 4-methylpent-1-ene, 1-decene, 1-dodecene, 1-hexadecene, andthe like.

Referring again to FIG. 2, the fluidized bed reactor 122 can include areaction zone 132 and a velocity reduction zone 134. The reaction zone132 can include a bed 136 that includes growing polymer particles,formed polymer particles and a minor amount of catalyst particlesfluidized by the continuous flow of the gaseous monomer and diluent toremove heat of polymerization through the reaction zone. Optionally,some of the re-circulated gases 124 can be cooled and compressed to formliquids that increase the heat removal capacity of the circulating gasstream when readmitted to the reaction zone. A suitable rate of gas flowcan be readily determined by experimentation. Make-up of gaseous monomerto the circulating gas stream can be at a rate equal to the rate atwhich particulate polymer product and monomer associated therewith iswithdrawn from the reactor and the composition of the gas passingthrough the reactor can be adjusted to maintain an essentially steadystate gaseous composition within the reaction zone. The gas leaving thereaction zone 132 can be passed to the velocity reduction zone 134 whereentrained particles are removed, for example, by slowing and fallingback to the reaction zone 132. If desired, finer entrained particles anddust can be removed in a separation system 138, such as a cyclone and/orfines filter. The gas 124 can be passed through a heat exchanger 144where at least a portion of the heat of polymerization can be removed.The gas can then be compressed in a compressor 142 and returned to thereaction zone 132. Alternately, compressor 142 can be located upstream(not shown) of exchanger 144. Additional reactor details and means foroperating the reactor 122 are described in, for example, U.S. Pat. Nos.3,709,853; 4,003,712; 4,011,382; 4,302,566; 4,543,399; 4,882,400;5,352,749; and 5,541,270; EP 0802202; and BE Patent No. 839,380.

The reactor temperature of the fluid bed process can be greater than 30°C., greater than 40° C., greater than 50° C., greater than 90° C.,greater than 100° C., greater than 110° C., greater than 120° C.,greater than 150° C., or higher. In general, the reactor temperature isoperated at a suitable temperature taking into account the sinteringtemperature of the polymer product within the reactor. Thus, the uppertemperature limit in one embodiment is the melting temperature of thepolyethylene copolymer produced in the reactor. However, highertemperatures may result in narrower MWDs, which can be improved by theaddition of a catalyst, or other co-catalysts, as described herein.

Hydrogen gas can be used in olefin polymerization to control the finalproperties of the polyolefin, such as described in the “PolypropyleneHandbook, at pages 76-78 (Hanser Publishers, 1996). Using certaincatalyst systems, increasing concentrations (partial pressures) ofhydrogen can increase a flow index such as MI of the polyethylenecopolymer generated. The MI can thus be influenced by the hydrogenconcentration. The amount of hydrogen in the polymerization can beexpressed as a mole ratio relative to the total polymerizable monomer,for example, ethylene, or a blend of ethylene and hexene or propylene.

The polymerization conditions in some embodiments include: a hydrogenconcentration in the range of from 50 ppm to 2000 ppm, or from 150 ppmto 600 ppm, or from 300 ppm to 450 ppm; an ethylene concentration in therange of from 35 mol % to 95 mol %, or from 45 mol % to 85 mol %, orfrom 55 mol % to 75 mol %; a comonomer concentration in the range offrom 0.2 mol % to 2 mol %, or from 0.7 mol % to 1.5 mol %, or from 0.9mol % to 1.3 mol %; a reactor pressure in the range of from 200 psig to500 psig, or from 270 psig to 320 psig, or from 280 psig to 305 psig;and a reactor temperature in the range of from 100° F. to 250° F., orfrom 160° F. to 205° F., or from 175° F. to 190° F. Other ranges aredisclosed by combining any lower endpoint of any individual range can beused with any upper endpoint of that range. Any range from one operatingparameter can be combined with any range from other operating parametersto define additional embodiments.

The gas phase reactor can be capable of producing from 10 kg of polymerper hour (25 lbs/hr) to 90,900 kg/hr (200,000 lbs/hr), or greater, andgreater than 455 kg/hr (1,000 lbs/hr), greater than 4.540 kg/hr (10,000lbs/hr), greater than 11,300 kg/hr (25,000 lbs/hr), greater than 15,900kg/hr (35,000 lbs/hr), and greater than 22,700 kg/hr (50,000 lbs/hr),and from 29,000 kg/hr (65,000 lbs/hr) to 45,500 kg/hr (100,000 lbs/hr)or from 45,450 kg/hr (100,000 lbs/hr) to 90,900 kg/hr (200,000 lbs/hr),such as 45,450 kg/hr (100,000 lbs/hr) to 68,175 kg/hr (150,000 lbs/hr),such as 45,450 kg/hr (100,000 lbs/hr) to 59,085 kg/hr (130,000 lbs/hr)alternatively from 68,175 kg/hr (150,000 lbs/hr) to 81,810 kg/hr(180,000 lbs/hr).

Polymerization Processes

In embodiments herein, the invention relates to polymerization processeswhere monomer (such as propylene and or ethylene), and optionallycomonomer, are contacted with a catalyst system comprising at least oneactivator, at least one support and at least two catalyst compounds,such as the metallocene compounds described above. The support, catalystcompounds, and activator may be combined in any order, and are combinedtypically prior to contacting with the monomers.

Monomers useful herein include substituted or unsubstituted C₂ to C₄₀alpha olefins, preferably C₂ to C₂₀ alpha olefins, preferably C₂ to C₁₂alpha olefins, preferably ethylene, propylene, butene, pentene, hexene,heptene, octene, nonene, decene, undecene, dodecene and isomers thereof.

In an embodiment of the invention, the monomer comprises propylene andan optional comonomers comprising one or more ethylene or C₄ to C₄₀olefins, preferably C₄ to C₂₀ olefins, or preferably C₆ to C₁₂ olefins.The C₄ to C₄₀ olefin monomers may be linear, branched, or cyclic. The C₄to C₄₀ cyclic olefins may be strained or unstrained, monocyclic orpolycyclic, and may optionally include heteroatoms and/or one or morefunctional groups.

In another embodiment of the invention, the monomer comprises ethyleneand optional comonomers comprising one or more C₃ to C₄₀ olefins,preferably C₄ to C₂₀ olefins, or preferably C₆ to C₁₂ olefins. The C₃ toC₄₀ olefin monomers may be linear, branched, or cyclic. The C₃ to C₄₀cyclic olefins may be strained or unstrained, monocyclic or polycyclic,and may optionally include heteroatoms and/or one or more functionalgroups.

Exemplary C₂ to C₄₀ olefin monomers and optional comonomers includeethylene, propylene, butene, pentene, hexene, heptene, octene, nonene,decene, undecene, dodecene, norbornene, norbornadiene,dicyclopentadiene, cyclopentene, cycloheptene, cyclooctene,cyclooctadiene, cyclododecene, 7-oxanorbornene, 7-oxanorbornadiene,substituted derivatives thereof, and isomers thereof, preferably hexene,heptene, octene, nonene, decene, dodecene, cyclooctene,1,5-cyclooctadiene, 1-hydroxy-4-cyclooctene, 1-acetoxy-4-cyclooctene,5-methylcyclopentene, cyclopentene, dicyclopentadiene, norbornene,norbornadiene, and their respective homologs and derivatives, preferablynorbornene, norbornadiene, and dicyclopentadiene.

In a preferred embodiment one or more dienes are present in the polymerproduced herein at up to 10 wt %, preferably at 0.00001 to 1.0 wt %,preferably 0.002 to 0.5 wt %, even more preferably 0.003 to 0.2 wt %,based upon the total weight of the composition. In some embodiments 500ppm or less of diene is added to the polymerization, preferably 400 ppmor less, preferably or 300 ppm or less. In other embodiments at least 50ppm of diene is added to the polymerization, or 100 ppm or more, or 150ppm or more.

Diolefin monomers useful in this invention include any hydrocarbonstructure, preferably C₄ to C₃₀, having at least two unsaturated bonds,wherein at least two of the unsaturated bonds are readily incorporatedinto a polymer by either a stereospecific or a non-stereospecificcatalyst(s). It is further preferred that the diolefin monomers beselected from alpha, omega-diene monomers (i.e., di-vinyl monomers).More preferably, the diolefin monomers are linear di-vinyl monomers,most preferably those containing from 4 to 30 carbon atoms. Examples ofpreferred dienes include butadiene, pentadiene, hexadiene, heptadiene,octadiene, nonadiene, decadiene, undecadiene, dodecadiene, tridecadiene,tetradecadiene, pentadecadiene, hexadecadiene, heptadecadiene,octadecadiene, nonadecadiene, icosadiene, heneicosadiene, docosadiene,tricosadiene, tetracosadiene, pentacosadiene, hexacosadiene,heptacosadiene, octacosadiene, nonacosadiene, triacontadiene,particularly preferred dienes include 1,6-heptadiene, 1,7-octadiene,1,8-nonadiene, 1,9-decadiene, 1,10-undecadiene, 1,11-dodecadiene,1,12-tridecadiene, 1,13-tetradecadiene, and low molecular weightpolybutadienes (M_(w) less than 1000 g/mol). Preferred cyclic dienesinclude cyclopentadiene, vinylnorbornene, norbornadiene, ethylidenenorbornene, divinylbenzene, dicyclopentadiene or higher ring containingdiolefins with or without substituents at various ring positions.

Polymerization processes according to the present disclosure can becarried out in any manner known in the art. Any suspension, slurry, highpressure tubular or autoclave process, or gas phase polymerizationprocess known in the art can be used under polymerizable conditions.Such processes can be run in a batch, semi-batch, or continuous mode.Heterogeneous polymerization processes (such as gas phase and slurryphase processes) are useful. A heterogeneous process is defined to be aprocess where the catalyst system is not soluble in the reaction media.Alternatively, in other embodiments, the polymerization process is nothomogeneous.

A homogeneous polymerization process is defined to be a process wherepreferably at least 90 wt % of the product is soluble in the reactionmedia. Alternatively, the polymerization process is not a bulk process.In a class of embodiments, a bulk process is defined to be a processwhere monomer concentration in all feeds to the reactor is preferably 70vol % or more. Alternatively, no solvent or diluent is present or addedin the reaction medium, (except for the small amounts used as thecarrier for the catalyst system or other additives, or amounts typicallyfound with the monomer; e.g., propane in propylene). In anotherembodiment, the process is a slurry process. As used herein the term“slurry polymerization process” means a polymerization process where asupported catalyst is employed and monomers are polymerized on thesupported catalyst particles. At least 95 wt % of polymer productsderived from the supported catalyst are in granular form as solidparticles (not dissolved in the diluent).

Suitable diluents/solvents for polymerization include non-coordinating,inert liquids. Examples include straight and branched-chainhydrocarbons, such as isobutane, butane, pentane, isopentane, hexanes,isohexane, heptane, octane, dodecane, and mixtures thereof; cyclic andalicyclic hydrocarbons, such as cyclohexane, cycloheptane,methylcyclohexane, methylcycloheptane, and mixtures thereof, such as canbe found commercially (Isopar™); perhalogenated hydrocarbons, such asperfluorinated C₄₋₁₀ alkanes, chlorobenzene, and aromatic andalkylsubstituted aromatic compounds, such as benzene, toluene,mesitylene, and xylene. Suitable solvents also include liquid olefinswhich may act as monomers or comonomers including ethylene, propylene,1-butene, 1-hexene, 1-pentene, 3-methyl-1-pentene, 4-methyl-1-pentene,1-octene, 1-decene, and mixtures thereof. In a preferred embodiment,aliphatic hydrocarbon solvents are used as the solvent, such asisobutane, butane, pentane, isopentane, hexanes, isohexane, heptane,octane, dodecane, and mixtures thereof; cyclic and alicyclichydrocarbons, such as cyclohexane, cycloheptane, methylcyclohexane,methylcycloheptane, and mixtures thereof. In another embodiment, thesolvent is not aromatic, preferably aromatics are present in the solventat less than 1 wt %, preferably less than 0.5 wt %, preferably less than0 wt % based upon the weight of the solvents.

In a preferred embodiment, the feed concentration of the monomers andcomonomers for the polymerization is 60 vol % solvent or less,preferably 40 vol % or less, or preferably 20 vol % or less, based onthe total volume of the feedstream. Preferably the polymerization is runin a bulk process.

Preferred polymerizations can be run at any temperature and/or pressuresuitable to obtain the desired ethylene polymers and as described above.Typical pressures include pressures in the range of from about 0.35 MPato about 10 MPa, preferably from about 0.45 MPa to about 6 MPa, orpreferably from about 0.5 MPa to about 4 MPa in some embodiments.

In some embodiments, hydrogen is present in the polymerization reactorat a partial pressure of 0.001 to 50 psig (0.007 to 345 kPa), preferablyfrom 0.01 to 25 psig (0.07 to 172 kPa), more preferably 0.1 to 10 psig(0.7 to 70 kPa).

In a class of embodiments, the polymerization is performed in the gasphase, preferably, in a fluidized bed gas phase process. Generally, in afluidized bed gas phase process used for producing polymers, a gaseousstream containing one or more monomers is continuously cycled through afluidized bed in the presence of a catalyst under reactive conditions.The gaseous stream is withdrawn from the fluidized bed and recycled backinto the reactor. Simultaneously, polymer product is withdrawn from thereactor and fresh monomer is added to replace the polymerized monomer.(See, for example, U.S. Pat. Nos. 4,543,399; 4,588,790; 5,028,670;5,317,036; 5,352,749; 5,405,922; 5,436,304; 5,453,471; 5,462,999;5,616,661; and 5,668,228; all of which are fully incorporated herein byreference.

In another embodiment of the invention, the polymerization is performedin the slurry phase. A slurry polymerization process generally operatesbetween 1 to about 50 atmosphere pressure range (15 psi to 735 psi, 103kPa to 5068 kPa) or even greater and temperatures as described above. Ina slurry polymerization, a suspension of solid, particulate polymer isformed in a liquid polymerization diluent medium to which monomer andcomonomers, along with catalysts, are added. The suspension includingdiluent is intermittently or continuously removed from the reactor wherethe volatile components are separated from the polymer and recycled,optionally after a distillation, to the reactor. The liquid diluentemployed in the polymerization medium is typically an alkane having from3 to 7 carbon atoms, preferably a branched alkane. The medium employedshould be liquid under the conditions of polymerization and relativelyinert. When a propane medium is used, the process is typically operatedabove the reaction diluent critical temperature and pressure. Often, ahexane or an isobutane medium is employed.

In an embodiment, a preferred polymerization technique useful in theinvention is referred to as a particle form polymerization, or a slurryprocess where the temperature is kept below the temperature at which thepolymer goes into solution. Such technique is known in the art, anddescribed in for instance U.S. Pat. No. 3,248,179. A preferredtemperature in the particle form process is within the range of about85° C. to about 110° C. Two preferred polymerization methods for theslurry process are those employing a loop reactor and those utilizing aplurality of stirred reactors in series, parallel, or combinationsthereof. Non-limiting examples of slurry processes include continuousloop or stirred tank processes. Also, other examples of slurry processesare described in U.S. Pat. No. 4,613,484, which is herein fullyincorporated by reference.

In another embodiment, the slurry process is carried out continuously ina loop reactor. The catalyst, as a slurry in isobutane or as a dry freeflowing powder, is injected regularly to the reactor loop, which isitself filled with circulating slurry of growing polymer particles in adiluent of isobutane containing monomer and comonomer. Hydrogen,optionally, may be added as a molecular weight control. In oneembodiment 500 ppm or less of hydrogen is added, or 400 ppm or less or300 ppm or less. In other embodiments at least 50 ppm of hydrogen isadded, or 100 ppm or more, or 150 ppm or more.

Reaction heat is removed through the loop wall since much of the reactoris in the form of a double-jacketed pipe. The slurry is allowed to exitthe reactor at regular intervals or continuously to a heated lowpressure flash vessel, rotary dryer and a nitrogen purge column insequence for removal of the isobutane diluent and all unreacted monomerand comonomers. The resulting hydrocarbon free powder is then compoundedfor use in various applications.

In a preferred embodiment, the catalyst system used in thepolymerization comprises no more than two catalyst compounds. A“reaction zone” also referred to as a “polymerization zone” is a vesselwhere polymerization takes place, for example a batch reactor. Whenmultiple reactors are used in either series or parallel configuration,each reactor is considered as a separate polymerization zone. For amulti-stage polymerization in both a batch reactor and a continuousreactor, each polymerization stage is considered as a separatepolymerization zone. In a preferred embodiment, the polymerizationoccurs in one reaction zone.

Useful reactor types and/or processes for the production of polyolefinpolymers include, but are not limited to, UNIPOL™ Gas Phase Reactors(available from Univation Technologies); INEOS™ Gas Phase Reactors andProcesses; Continuous Flow Stirred-Tank (CSTR) reactors (solution andslurry); Plug Flow Tubular reactors (solution and slurry); Slurry:(e.g., Slurry Loop (single or double loops)) (available from ChevronPhillips Chemical Company) and (Series Reactors) (available from MitsuiChemicals)); BORSTAR™ Process and Reactors (slurry combined with gasphase); and Multi-Zone Circulating Reactors (MZCR) such as SPHERIZONE™Reactors and Process available from Lyondell Basell.

In several classes of embodiments, the catalyst activity of thepolymerization reaction is at least 4,250 g/g*cat or greater, at least4,750 g/g*cat or greater, at least 5,000 g/g*cat or greater, at least6,250 g/g*cat or greater, at least 8,500 g/g*cat or greater, at least9,000 g/g*cat or greater, at least 9,500 g/g*cat or greater, or at least9,700 g/g*cat or greater.

In a preferred embodiment, the polymerization:

1) is conducted at temperatures of 0 to 300° C. (preferably 25 to 150°C., preferably 40 to 120° C., preferably 45 to 85° C.);

2) is conducted at a pressure of atmospheric pressure to 10 MPa(preferably 0.35 to 10 MPa, preferably from 0.45 to 6 MPa, preferablyfrom 0.5 to 4 MPa);

3) is conducted in an aliphatic hydrocarbon solvent (such as isobutane,butane, pentane, isopentane, hexane, isohexane, heptane, octane,dodecane, and mixtures thereof; cyclic and alicyclic hydrocarbons, suchas cyclohexane, cycloheptane, methylcyclohexane, methylcycloheptane, andmixtures thereof; preferably where aromatics are preferably present inthe solvent at less than 1 wt %, preferably less than 0.5 wt %,preferably at 0 wt % based upon the weight of the solvents);

4) wherein the catalyst system used in the polymerization preferablycomprises bis(1-ethyl-indenyl) zirconium dimethyl,bis(n-propyl-cyclopentadienyl) hafnium dimethyl, a support such assilica, and an activator (such as methylalumoxane, N,N-dimethylaniliniumtetrakis(pentafluorophenyl)borate, or N,N-dimethylaniliniumtetrakis(perfluoronaphthyl)borate);

5) the polymerization preferably occurs in one reaction zone;

6) the productivity of the catalyst compound is at least 4,250 g/g*cator greater, at least 4,750 g/g*cat or greater, at least 5,000 g/g*cat orgreater, at least 6,250 g/g*cat or greater, at least 8,500 g/g*cat orgreater, at least 9,000 g/g*cat or greater, at least 9,500 g/g*cat orgreater, or at least 9,700 g/g*cat or greater;

7) optionally scavengers (such as trialkyl aluminum compounds) areabsent (e.g. present at zero mol %, alternately the scavenger is presentat a molar ratio of scavenger metal to transition metal of less than100:1, preferably less than 50:1, preferably less than 15:1, preferablyless than 10:1); and

8) optionally hydrogen is present in the polymerization reactor at apartial pressure of 0.001 to 50 psig (0.007 to 345 kPa) (preferably from0.01 to 25 psig (0.07 to 172 kPa), more preferably 0.1 to 10 psig (0.7to 70 kPa)).

Polyolefin Products

In an embodiment, the process described herein produces polyethylenecompositions including homopolymers and copolymers of one, two, three,four or more C₂ to C₄₀ olefin monomers, for example, C₂ to C₂₀ α-olefinmonomers.

For example, the polyethylene compositions include copolymers of a C₂ toC₄₀ olefin and one, two or three or more different C₂ to C₄₀ olefins,(where the C₂ to C₄₀ olefins are preferably C₃ to C₂₀ olefins,preferably are C₃ to C₁₂ α-olefin, preferably are propylene, butene,hexene, octene, decene, dodecene, preferably propylene, butene, hexene,octene, or a mixture thereof).

The polyethylene composition may comprise from 99.0 to about 80.0 wt %,99.0 to 85.0 wt %, 99.0 to 87.5 wt %, 99.0 to 90.0 wt %, 99.0 to 92.5 wt%, 99.0 to 95.0 wt %, or 99.0 to 97.0 wt %, of polymer units derivedfrom ethylene and about 1.0 to about 20.0 wt %, 1.0 to 15.0 wt %, 0.5 to12.5 wt %, 1.0 to 10.0 wt %, 1.0 to 7.5 wt %, 1.0 to 5.0 wt %, or 1.0 to3.0 wt % of polymer units derived from one or more C₃ to C₂₀ α-olefincomonomers, preferably C₃ to C₁₀ α-olefins, and more preferably C₄ to C₈α-olefins, such as hexene and octene. The α-olefin comonomer may belinear or branched, and two or more comonomers may be used, if desired.

Examples of suitable comonomers include propylene, butene, 1-pentene;1-pentene with one or more methyl, ethyl, or propyl substituents;1-hexene; 1-hexene with one or more methyl, ethyl, or propylsubstituents; 1-heptene; 1-heptene with one or more methyl, ethyl, orpropyl substituents; 1-octene; 1-octene with one or more methyl, ethyl,or propyl substituents; 1-nonene; 1-nonene with one or more methyl,ethyl, or propyl substituents; ethyl, methyl, or dimethyl-substituted1-decene; 1-dodecene; and styrene. Particularly suitable comonomersinclude 1-butene, 1-hexene, and 1-octene, 1-hexene, and mixturesthereof.

The polyethylene composition may have a melt index, I_(2.16), accordingto the test method listed below, of ≥ about 0.10 g/10 min, e.g., ≥ about0.15 g/10 min, ≥ about 0.18 g/10 min, ≥ about 0.20 g/10 min, ≥ about0.22 g/10 min, ≥ about 0.25 g/10 min, ≥ about 0.28 g/10 min, or ≥ about0.30 g/10 min and, also, a melt index (I_(2.16))≤ about 3.00 g/10 min,e.g., ≤ about 2.00 g/10 min, ≤ about 1.00 g/10 min, ≤ about 0.70 g/10min, ≤ about 0.50 g/10 min, ≤ about 0.40 g/10 min, or ≤ about 0.30 g/10min. Ranges expressly disclosed include, but are not limited to, rangesformed by combinations any of the above-enumerated values, e.g., about0.10 to about 0.30, about 0.15 to about 0.25, about 0.18 to about 0.22g/10 min, etc. In another embodiment, the melt index could be about 0.1g/10 min to about 30 g/10 min, such as about 20 g/10 min to about 30g/10 min.

The polyethylene composition may have a high load melt index (HLMI)(I_(21.6)) in accordance with the test method listed below of from 1 to60 g/10 min, 5 to 40 g/10 min, 5 to 50 g/10 min, 15 to 50 g/10 min, or20 to 50 g/10 min.

The polyethylene composition may have a melt index ratio (MIR), from 10to 90, from 20 to 45, from 25 to 60, alternatively, from 30 to 55,alternatively, from 35 to 55, and alternatively, from 35 to 50 or 35 to45. MIR is defined as I_(21.6)/I_(2.16).

The polyethylene composition may have a density of about 0.920 g/cm³,about 0.918 g/cm³, or ≥ about 0.910 g/cm³, e.g., ≥ about 0.919 g/cm³, ≥about 0.92 g/cm³, ≥ about 0.930 g/cm³, ≥ about 0.932 g/cm³.Additionally, the polyethylene composition may have a density ≤ about0.945 g/cm³, e.g., ≤ about 0.940 g/cm³, ≤ about 0.937 g/cm³, ≤ about0.935 g/cm³, ≤ about 0.933 g/cm³, or ≤ about 0.930 g/cm³. Rangesexpressly disclosed include, but are not limited to, ranges formed bycombinations any of the above-enumerated values, e.g., about 0.919 toabout 0.945 g/cm³, 0.920 to 0.930 g/cm³, 0.925 to 0.935 g/cm³, 0.920 to0.940 g/cm³, etc. Density is determined in accordance with the testmethod listed below.

The polyethylene composition may have a molecular weight distribution(MWD, defined as M_(w)/M_(n)) of about 2 to about 12, about 5 to about10.5 or 11, about 2.5 to about 5.5, preferably 4.0 to 5.0 and about 4.4to 5.0.

In a class of embodiments, the polyethylene composition comprises atleast 65 wt % ethylene derived units and from 0.1 to 35 wt % of C₃-C₁₂olefin comonomer derived units, based upon the total weight of thepolyethylene composition; wherein the polyethylene composition has:

-   -   a) an RCI,m of 100 kg/mol or greater, alternatively, 110 kg/mol        or greater, alternatively, 125 kg/mol or greater, alternatively,        150 kg/mol or greater, alternatively, 170 kg/mol or greater, and        alternatively, 185 kg/mol or greater;        and one or both of:    -   b) a Tw₁-Tw₂ value of from −16 to −38° C., alternatively, a        Tw₁-Tw₂ value of from −23 to −36° C., and alternatively, a        Tw₁-Tw₂ value of from −23 to −33° C.; and    -   c) an Mw₁/Mw₂ value of at least 0.9, alternatively, an Mw₁/Mw₂        value of from 0.9 to 4, and alternatively, an Mw₁/Mw₂ value of        from 1.25 to 4;

and one or more of the following:

-   -   d) a density of from 0.890 g/cm³ to 0.940 g/cm³;    -   e) a melt index (MI) of from 0.1 g/10 min to 30 g/10 min,        alternatively, a melt index (MI) of from 0.1 g/10 min to 6 g/10        min;    -   f) a melt index ratio (I₂₁/I₂) of from 10 to 90;    -   g) an M_(w)/M_(n) of from 2 to 12;    -   h) an M_(z)/M_(w) of from 2.5 to 5.0;    -   i) an M_(z)/M_(n) of from 10 to 40; and    -   j) a g′(vis) of 0.900 or greater, alternatively, 0.930 or        greater, alternatively, 0.940 or greater, and alternatively        0.994 or greater.

This invention also relates to polyethylene compositions comprising atleast 65 wt % ethylene derived units and from 0.1 to 35 wt % of C₃-C₁₂olefin comonomer derived units, based upon the total weight of thepolyethylene composition; wherein the polyethylene composition has:

-   -   a) an RCI,m of 100 kg/mol or greater, such as 150 kg/mol or        greater;        and one or more of the following:    -   b) a density of from 0.890 g/cm³ to 0.940 g/cm³;    -   c) a melt index (MI) of from 0.1 g/10 min to 30 g/10 min;    -   d) a melt index ratio (I₂₁/I₂) of from 10 to 90, such 25 to 55,        or 30 to 40;    -   e) an M_(w)/M_(n) of from 2 to 16, such as 9 to 14, or 10 to 14;    -   f) an M_(z)/M_(w) of from 2.5 to 5.0;    -   g) an M_(z)/M_(n) of from 10 to 50, such as 25 to 50, or 25 to        45; and    -   h) a g′ (vis) of 0.900 or greater.

In any of the embodiments described herein, the polyethylene compositionmay be a multimodal polyethylene composition such as a bimodalpolyethylene composition. As used herein, “multimodal” means that thereare at least two distinguishable peaks in a molecular weightdistribution curve (as determined using gel permeation chromatography(GPC) or other recognized analytical technique) of a polyethylenecomposition. For example, if there are two distinguishable peaks in themolecular weight distribution curve such composition may be referred toas bimodal composition. Typically, if there is only one peak (e.g.,monomodal), no obvious valley between the peaks, either one of the peaksis not considered as a distinguishable peak, or both peaks are notconsidered as distinguishable peaks, then such a composition may bereferred to as non-bimodal. For example, in U.S. Pat. Nos. 8,846,841 and8,691,715, FIGS. 1-5 illustrate representative bimodal molecular weightdistribution curves. In these figures, there is a valley between thepeaks, and the peaks can be separated or deconvoluted. Often, a bimodalmolecular weight distribution is characterized as having an identifiablehigh molecular weight component (or distribution) and an identifiablelow molecular weight component (or distribution). In contrast, in U.S.Pat. Nos. 8,846,841 and 8,691,715, FIGS. 6-11 illustrate representativenon-bimodal molecular weight distribution curves. These include unimodalmolecular weight distributions as well as distribution curves containingtwo peaks that cannot be easily distinguished, separated, ordeconvoluted.

In any of the embodiments described herein, the polyethylene compositionmay have an internal unsaturation as measured by ¹H NMR (see below forthe test method) of more than 0.2 total internal unsaturations perthousand carbon atoms, alternatively, more than 0.3 total internalunsaturations per thousand carbon atoms, alternatively, more than 0.32total internal unsaturations per thousand carbon atoms, alternatively,more than 0.38 total internal unsaturations per thousand carbon atoms,and alternatively, more than 0.4 total internal unsaturations perthousand carbon atoms.

Blends

In another embodiment, the polymer (preferably the polyethylene orpolypropylene) or polyethylene composition produced herein is combinedwith one or more additional polymers in a blend prior to being formedinto a film, molded part, or other article. As used herein, a “blend”may refer to a dry or extruder blend of two or more different polymers,and in-reactor blends, including blends arising from the use of multi ormixed catalyst systems in a single reactor zone, and blends that resultfrom the use of one or more catalysts in one or more reactors under thesame or different conditions (e.g., a blend resulting from in seriesreactors (the same or different) each running under different conditionsand/or with different catalysts).

Useful additional polymers include other polyethylenes, isotacticpolypropylene, highly isotactic polypropylene, syndiotacticpolypropylene, random copolymer of propylene and ethylene, and/orbutene, and/or hexene, polybutene, ethylene vinyl acetate, LDPE, LLDPE,HDPE, ethylene vinyl acetate, ethylene methyl acrylate, copolymers ofacrylic acid, polymethylmethacrylate or any other polymers polymerizableby a high-pressure free radical process, polyvinylchloride,polybutene-1, isotactic polybutene, ABS resins, ethylene-propylenerubber (EPR), vulcanized EPR, EPDM, block copolymer, styrenic blockcopolymers, polyamides, polycarbonates, PET resins, cross linkedpolyethylene, copolymers of ethylene and vinyl alcohol (EVOH), polymersof aromatic monomers such as polystyrene, poly-1 esters, polyacetal,polyvinylidine fluoride, polyethylene glycols, and/or polyisobutylene.

End Uses

Any of the foregoing polymers and compositions in combination withoptional additives (see, for example, U.S. Patent ApplicationPublication No. 2016/0060430, paragraphs [0082]-[0093]) may be used in avariety of end-use applications. Such end uses may be produced bymethods known in the art. End uses include polymer products and productshaving specific end-uses. Exemplary end uses are films, film-basedproducts, diaper backsheets, housewrap, wire and cable coatingcompositions, articles formed by molding techniques, e.g., injection orblow molding, extrusion coating, foaming, casting, and combinationsthereof. End uses also include products made from films, e.g., bags,packaging, and personal care films, pouches, medical products, such asfor example, medical films and intravenous (IV) bags.

Films

Films include monolayer or multilayer films. Films include those filmstructures and film applications known to those skilled in the art.Specific end use films include, for example, blown films, cast films,stretch films, stretch/cast films, stretch cling films, stretch handwrapfilms, machine stretch wrap, shrink films, shrink wrap films, greenhouse films, laminates, and laminate films. Exemplary films are preparedby any conventional technique known to those skilled in the art, such asfor example, techniques utilized to prepare blown, extruded, and/or caststretch and/or shrink films (including shrink-on-shrink applications).

In one embodiment, multilayer films or multiple-layer films may beformed by methods well known in the art. The total thickness ofmultilayer films may vary based upon the application desired. A totalfilm thickness of about 5-100 μm, more typically about 10-50 μm, issuitable for most applications. Those skilled in the art will appreciatethat the thickness of individual layers for multilayer films may beadjusted based on desired end-use performance, resin or copolymeremployed, equipment capability, and other factors. The materials formingeach layer may be coextruded through a coextrusion feedblock and dieassembly to yield a film with two or more layers adhered together butdiffering in composition. Coextrusion can be adapted for use in bothcast film or blown film processes. Exemplary multilayer films have atleast two, at least three, or at least four layers. In one embodimentthe multilayer films are composed of five to ten layers.

To facilitate discussion of different film structures, the followingnotation is used herein. Each layer of a film is denoted “A” or “B”.Where a film includes more than one A layer or more than one B layer,one or more prime symbols (′, ″, ′″, etc.) are appended to the A or Bsymbol to indicate layers of the same type that can be the same or candiffer in one or more properties, such as chemical composition, density,melt index, thickness, etc. Finally, the symbols for adjacent layers areseparated by a slash (/). Using this notation, a three-layer film havingan inner layer disposed between two outer layers would be denotedA/B/A′. Similarly, a five-layer film of alternating layers would bedenoted A/B/A′/B′/A″. Unless otherwise indicated, the left-to-right orright-to-left order of layers does not matter, nor does the order ofprime symbols; e.g., an A/B film is equivalent to a B/A film, and anA/A′/B/A″ film is equivalent to an A/B/A′/A″ film, for purposesdescribed herein. The relative thickness of each film layer is similarlydenoted, with the thickness of each layer relative to a total filmthickness of 100 (dimensionless) indicated numerically and separated byslashes; e.g., the relative thickness of an A/B/A′ film having A and A′layers of 10 μm each and a B layer of 30 μm is denoted as 20/60/20.

The thickness of each layer of the film, and of the overall film, is notparticularly limited, but is determined according to the desiredproperties of the film. Typical film layers have a thickness of fromabout 1 to about 1000 μm, more typically from about 5 to about 100 μm,and typical films have an overall thickness of from about 10 to about100 μm.

In some embodiments, and using the nomenclature described above, thepresent invention provides for multilayer films with any of thefollowing exemplary structures: (a) two-layer films, such as A/B andB/B′; (b) three-layer films, such as A/B/A′, A/A′/B, B/A/B′ and B/B′/B″;(c) four-layer films, such as A/A′/A″/B, A/A′/B/A″, A/A′/B/B′,A/B/A′/B′, A/B/B′/A′, B/A/A′/B′, A/B/B′/B″, B/A/B′/B″ and B/B′/B″/B′″;(d) five-layer films, such as A/A′/A″/A′″/B, A/A′/A″/B/A″″,A/A′/B/A″/A′″, A/A′/A″/B/B′, A/A′/B/A″/B′, A/A′/B/B′/A″, A/B/A′/B′/A″,A/B/A′/A″/B, B/A/A′/A″/B′, A/A′/B/B′/B″, A/B/A′/B′/B″, A/B/B′/B″/A′,B/A/A′/B′/B″, B/A/B′/A′/B″, B/A/B′/B″/N, A/B/B′/B″/B′″, B/A/B′/B″/B′″,B/B′/A/B″/B′″, and B/B′/B″/B′″/B″″; and similar structures for filmshaving six, seven, eight, nine, twenty-four, forty-eight, sixty-four,one hundred, or any other number of layers. It should be appreciatedthat films having still more layers.

In any of the embodiments above, one or more A layers can be replacedwith a substrate layer, such as glass, plastic, paper, metal, etc., orthe entire film can be coated or laminated onto a substrate. Thus,although the discussion herein has focused on multilayer films, thefilms may also be used as coatings for substrates such as paper, metal,glass, plastic, and other materials capable of accepting a coating.

The films can further be embossed, or produced or processed according toother known film processes. The films can be tailored to specificapplications by adjusting the thickness, materials and order of thevarious layers, as well as the additives in or modifiers applied to eachlayer.

Preferably, the articles (preferably films) produced herein have anaverage MD/TD modulus ((MD+TD)/2)) that is greater than X, whereX=(2,065,292*density of ethylene polymer)−1,872,345, preferably theinventive films have an average modulus of 1.2*X, preferably 1.3*X,preferably 1.4*X.

Preferably, the articles (preferably films) produced herein have anaverage MD/TD modulus of between 30,000 psi and 40,000 psi.

Preferably, the articles (preferably films) produced herein have a dartdrop impact resistance of 600 g/mil or greater.

Preferably, the articles (preferably films) produced herein have a dartdrop impact resistance of 700 g/mil or greater.

Preferably, the films produced herein have an Elmendorf tear resistanceof 300 g/mil or greater in the machine direction (MD).

Preferably, the preferably films produced herein have an Elmendorf tearresistance of 200 g/mil or greater in the machine direction (MD),preferably 300 g/mil or more, preferably 350 g/mil or more.

Preferably, the articles (preferably films) produced herein have a hazeof 12% or less.

Preferably, the ethylene polymers produced herein have an MIR of 35 to55, and a film produced therefrom has an Elmendorf tear resistance of300 g/mil (or at least 450 g/mil or greater or at least 500 g/mil orgreater) in the machine direction (MD), and/or a dart drop impactresistance of at least 500 g/mil or greater (or at least 750 g/mil orgreater, or at least 800 g/mil or greater).

Stretch Films

The polymers and compositions as described above may be utilized toprepare stretch films. Stretch films are widely used in a variety ofbundling and packaging applications. The term “stretch film” indicatesfilms capable of stretching and applying a bundling force, and includesfilms stretched at the time of application as well as “pre-stretched”films, i.e., films which are provided in a pre-stretched form for usewithout additional stretching. Stretch films can be monolayer films ormultilayer films, and can include conventional additives, such ascling-enhancing additives such as tackifiers, and non-cling or slipadditives, to tailor the slip/cling properties of the film.

Shrink Films

The polymers and compositions as described above may be utilized toprepare shrink films. Shrink films, also referred to as heat-shrinkablefilms, are widely used in both industrial and retail bundling andpackaging applications. Such films are capable of shrinking uponapplication of heat to release stress imparted to the film during orsubsequent to extrusion. The shrinkage can occur in one direction or inboth longitudinal and transverse directions. Conventional shrink filmsare described, for example, in WO 2004/022646.

Industrial shrink films are commonly used for bundling articles onpallets. Typical industrial shrink films are formed in a single bubbleblown extrusion process to a thickness of about 80 to 200 μm, andprovide shrinkage in two directions, typically at a machine direction(MD) to transverse direction (TD) ratio of about 60:40.

Retail films are commonly used for packaging and/or bundling articlesfor consumer use, such as, for example, in supermarket goods. Such filmsare typically formed in a single bubble blown extrusion process to athickness of about 35 to 80, μm, with a typical MD:TD shrink ratio ofabout 80:20.

Films may be used in “shrink-on-shrink” applications.“Shrink-on-shrink,” as used herein, refers to the process of applying anouter shrink wrap layer around one or more items that have already beenindividually shrink wrapped (herein, the “inner layer” of wrapping). Inthese processes, it is desired that the films used for wrapping theindividual items have a higher melting (or shrinking) point than thefilm used for the outside layer. When such a configuration is used, itis possible to achieve the desired level of shrinking in the outerlayer, while preventing the inner layer from melting, further shrinking,or otherwise distorting during shrinking of the outer layer. Some filmsdescribed herein have been observed to have a sharp shrinking point whensubjected to heat from a heat gun at a high heat setting, whichindicates that they may be especially suited for use as the inner layerin a variety of shrink-on-shrink applications.

Greenhouse Films

The polymers and compositions as described above may be utilized toprepare stretch to prepare greenhouse films. Greenhouse films aregenerally heat retention films that, depending on climate requirements,retain different amounts of heat. Less demanding heat retention filmsare used in warmer regions or for spring time applications. Moredemanding heat retention films are used in the winter months and incolder regions.

Bags

Bags include those bag structures and bag applications known to thoseskilled in the art. Exemplary bags include shipping sacks, trash bagsand liners, industrial liners, produce bags, and heavy duty bags.

Packaging

Packaging includes those packaging structures and packaging applicationsknown to those skilled in the art. Exemplary packaging includes flexiblepackaging, food packaging, e.g., fresh cut produce packaging, frozenfood packaging, bundling, packaging and unitizing a variety of products.Applications for such packaging include various foodstuffs, rolls ofcarpet, liquid containers, and various like goods normally containerizedand/or palletized for shipping, storage, and/or display.

Blow Molded Articles

The polymers and compositions described above may also be used in blowmolding processes and applications. Such processes are well known in theart, and involve a process of inflating a hot, hollow thermoplasticpreform (or parison) inside a closed mold. In this manner, the shape ofthe parison conforms to that of the mold cavity, enabling the productionof a wide variety of hollow parts and containers.

In a typical blow molding process, a parison is formed between moldhalves and the mold is closed around the parison, sealing one end of theparison and closing the parison around a mandrel at the other end. Airis then blown through the mandrel (or through a needle) to inflate theparison inside the mold. The mold is then cooled and the part formedinside the mold is solidified. Finally, the mold is opened and themolded part is ejected. The process lends itself to any design having ahollow shape, including but not limited to bottles, tanks, toys,household goods, automobile parts, and other hollow containers and/orparts.

Blow molding processes may include extrusion and/or injection blowmolding. Extrusion blow molding is typically suited for the formation ofitems having a comparatively heavy weight, such as greater than about 12ounces, including but not limited to food, laundry, or waste containers.Injection blow molding is typically used to achieve accurate and uniformwall thickness, high quality neck finish, and to process polymers thatcannot be extruded. Typical injection blow molding applications include,but are not limited to, pharmaceutical, cosmetic, and single servingcontainers, typically weighing less than 12 ounces.

Injection Molded Articles

The polymers and compositions described above may also be used ininjection molded applications. Injection molding is a process commonlyknown in the art, and is a process that usually occurs in a cyclicalfashion. Cycle times generally range from 10 to 100 seconds and arecontrolled by the cooling time of the polymer or polymer blend used.

In a typical injection molding cycle, polymer pellets or powder are fedfrom a hopper and melted in a reciprocating screw type injection moldingmachine. The screw in the machine rotates forward, filling a mold withmelt and holding the melt under high pressure. As the melt cools in themold and contracts, the machine adds more melt to the mold tocompensate. Once the mold is filled, it is isolated from the injectionunit and the melt cools and solidifies. The solidified part is ejectedfrom the mold and the mold is then closed to prepare for the nextinjection of melt from the injection unit.

Injection molding processes offer high production rates, goodrepeatability, minimum scrap losses, and little to no need for finishingof parts. Injection molding is suitable for a wide variety ofapplications, including containers, household goods, automobilecomponents, electronic parts, and many other solid articles.

Extrusion Coating

The polymers and compositions described above may be used in extrusioncoating processes and applications. Extrusion coating is a plasticfabrication process in which molten polymer is extruded and applied ontoa non-plastic support or substrate, such as paper or aluminum in orderto obtain a multi-material complex structure. This complex structuretypically combines toughness, sealing and resistance properties of thepolymer formulation with barrier, stiffness or aesthetics attributes ofthe non-polymer substrate. In this process, the substrate is typicallyfed from a roll into a molten polymer as the polymer is extruded from aslot die, which is similar to a cast film process. The resultantstructure is cooled, typically with a chill roll or rolls, and wouldinto finished rolls.

Extrusion coating materials are typically used in food and non-foodpackaging, pharmaceutical packaging, and manufacturing of goods for theconstruction (insulation elements) and photographic industries (paper).

Foamed Articles

The polymers and compositions described above may be used in foamedapplications. In an extrusion foaming process, a blowing agent, such as,for example, carbon dioxide, nitrogen, or a compound that decomposes toform carbon dioxide or nitrogen, is injected into a polymer melt bymeans of a metering unit. The blowing agent is then dissolved in thepolymer in an extruder, and pressure is maintained throughout theextruder. A rapid pressure drop rate upon exiting the extruder creates afoamed polymer having a homogenous cell structure. The resulting foamedproduct is typically light, strong, and suitable for use in a wide rangeof applications in industries such as packaging, automotive, aerospace,transportation, electric and electronics, and manufacturing.

Wire and Cable Applications

Also provided are electrical articles and devices including one or morelayers formed of or comprising the polymers and compositions describedabove. Such devices include, for example, electronic cables, computerand computer-related equipment, marine cables, power cables,telecommunications cables or data transmission cables, and combinedpower/telecommunications cables.

Electrical devices described herein can be formed by methods well knownin the art, such as by one or more extrusion coating steps in areactor/extruder equipped with a cable die. Such cable extrusionapparatus and processes are well known. In a typical extrusion method,an optionally heated conducting core is pulled through a heatedextrusion die, typically a cross-head die, in which a layer of meltedpolymer composition is applied. Multiple layers can be applied byconsecutive extrusion steps in which additional layers are added, or,with the proper type of die, multiple layers can be addedsimultaneously. The cable can be placed in a moisture curingenvironment, or allowed to cure under ambient conditions.

Test Methods

¹H NMR

¹H NMR data was collected at 393K in a 10 mm probe using a Brukerspectrometer with a ¹H frequency of 400 MHz (available from AgilentTechnologies, Santa Clara, Calif.). Data was recorded using a maximumpulse width of 45° C., 5 seconds between pulses and signal averaging 512transients. Spectral signals were integrated and the number ofunsaturation types per 1000 carbons was calculated by multiplying thedifferent groups by 1000 and dividing the result by the total number ofcarbons. M_(n) was calculated by dividing the total number ofunsaturated species into 14,000, and has units of g/mol.

TREF Method

Unless otherwise indicated, the TREF-LS data reported herein weremeasured using an analytical size TREF instrument (Polymerchar, Spain),with a column of the following dimension: inner diameter (ID) 7.8 mm andouter diameter (OD) 9.53 mm and a column length of 150 mm. The columnwas filled with steel beads. 0.5 mL of a 6.4% (w/v) polymer solution inorthodichlorobenzene (ODCB) containing 6 g BHT/4 L were charged onto thecolumn and cooled from 140° C. to 25° C. at a constant cooling rate of1.0° C./min. Subsequently, the ODCB was pumped through the column at aflow rate of 1.0 ml/min and the column temperature was increased at aconstant heating rate of 2° C./min to elute the polymer. The polymerconcentration in the eluted liquid was detected by means of measuringthe absorption at a wavenumber of 2857 cm⁻¹ using an infrared detector.The concentration of the ethylene-α-olefin copolymer in the elutedliquid was calculated from the absorption and plotted as a function oftemperature. The molecular weight of the ethylene-α-olefin copolymer inthe eluted liquid was measured by light scattering using a MinidawnTristar light scattering detector (Wyatt, Calif, USA). The molecularweight was also plotted as a function of temperature.

GPC 4D Procedure: Molecular Weight, Comonomer Composition and Long ChainBranching Determination by GPC-IR Hyphenated with Multiple Detectors

The distribution and the moments of molecular weight (M_(w), M_(n),M_(w)/M_(n), etc.), the comonomer content (C₂, C₃, C₆, etc.) and thebranching index (g′vis) are determined by using a high temperature GelPermeation Chromatography (Polymer Char GPC-IR) equipped with amultiple-channel band-filter based Infrared detector IR5, an 18-anglelight scattering detector and a viscometer. Three Agilent PLgel 10-μmMixed-B LS columns are used to provide polymer separation. Aldrichreagent grade 1,2,4-trichlorobenzene (TCB) with 300 ppm antioxidantbutylated hydroxytoluene (BHT) is used as the mobile phase. The TCBmixture is filtered through a 0.1 μm Teflon filter and degassed with anonline degasser before entering the GPC instrument. The nominal flowrate is 1.0 ml/min and the nominal injection volume is 200 μL. The wholesystem including transfer lines, columns, and detectors are contained inan oven maintained at 145° C. The polymer sample is weighed and sealedin a standard vial with 80 μL flow marker (Heptane) added to it. Afterloading the vial in the autosampler, polymer is automatically dissolvedin the instrument with 8 ml added TCB solvent. The polymer is dissolvedat 160° C. with continuous shaking for about 1 hour for PE samples or 2hour for PP samples. The TCB densities used in concentration calculationare 1.463 g/ml at about 23° C. temperature and 1.284 g/ml at 145° C. Thesample solution concentration is from 0.2 to 2.0 mg/ml, with lowerconcentrations being used for higher molecular weight samples. Theconcentration (c), at each point in the chromatogram is calculated fromthe baseline-subtracted IR5 broadband signal intensity (I), using thefollowing equation: c=βI, where β is the mass constant. The massrecovery is calculated from the ratio of the integrated area of theconcentration chromatography over elution volume and the injection masswhich is equal to the pre-determined concentration multiplied byinjection loop volume. The conventional molecular weight (IR MW) isdetermined by combining universal calibration relationship with thecolumn calibration which is performed with a series of monodispersedpolystyrene (PS) standards ranging from 700 to 10M gm/mole. The MW ateach elution volume is calculated with following equation:

${{\log\mspace{11mu} M} = {\frac{\log\left( {K_{PS}/K} \right)}{a + 1} + {\frac{a_{PS} + 1}{a + 1}\log\mspace{11mu} M_{PS}}}},$where the variables with subscript “PS” stand for polystyrene whilethose without a subscript are for the test samples. In this method,α_(PS)=0.67 and K_(PS)=0.000175 while α and K are for other materials ascalculated and published in literature (Sun, T. et al. Macromolecules2001, 34, 6812), except that for purposes of this invention and claimsthereto, α=0.695 and K=0.000579 for linear ethylene polymers, α=0.705and K=0.0002288 for linear propylene polymers, α=0.695 and K=0.000181for linear butene polymers, α is 0.695 and K is0.000579*(1−0.0087*w2b+0.000018*(w2b){circumflex over ( )}2) forethylene-butene copolymer where w2b is a bulk weight percent of butenecomonomer, a is 0.695 and K is 0.000579*(1−0.0075*w2b) forethylene-hexene copolymer where w2b is a bulk weight percent of hexenecomonomer, and a is 0.695 and K is 0.000579*(1−0.0077*w2b) forethylene-octene copolymer where w2b is a bulk weight percent of octenecomonomer. Concentrations are expressed in g/cm³, molecular weight isexpressed in g/mole, and intrinsic viscosity (hence K in theMark-Houwink equation) is expressed in dL/g unless otherwise noted.

The comonomer composition is determined by the ratio of the IR5 detectorintensity corresponding to CH₂ and CH₃ channel calibrated with a seriesof PE and PP homo/copolymer standards whose nominal value arepredetermined by NMR or FTIR. In particular, this provides the methylsper 1000 total carbons (CH₃/1000TC) as a function of molecular weight.The short-chain branch (SCB) content per 1000TC (SCB/1000TC) is thencomputed as a function of molecular weight by applying a chain-endcorrection to the CH₃/1000TC function, assuming each chain to be linearand terminated by a methyl group at each end. The wt % comonomer is thenobtained from the following expression in which f is 0.3, 0.4, 0.6, 0.8,and so on for C₃, C₄, C₆, C₈, and so on co-monomers, respectively:w2=f*SCB/1000TC.

The bulk composition of the polymer from the GPC-IR and GPC-4D analysesis obtained by considering the entire signals of the CH₃ and CH₂channels between the integration limits of the concentrationchromatogram. First, the following ratio is obtained

${{Bulk}\mspace{14mu}{IR}\mspace{14mu}{ratio}} = {\frac{{Area}\mspace{14mu}{of}\mspace{14mu}{CH}_{3}\mspace{14mu}{signal}\mspace{14mu}{within}\mspace{14mu}{integration}\mspace{14mu}{limits}}{{Area}\mspace{14mu}{of}\mspace{14mu}{CH}_{2}\mspace{14mu}{signal}\mspace{14mu}{within}\mspace{14mu}{integration}\mspace{14mu}{limits}}.}$

Then the same calibration of the CH₃ and CH₂ signal ratio, as mentionedpreviously in obtaining the CH3/1000TC as a function of molecularweight, is applied to obtain the bulk CH3/1000TC. A bulk methyl chainends per 1000TC (bulk CH3 end/1000TC) is obtained by weight-averagingthe chain-end correction over the molecular-weight range. Thenw2b=f*bulk CH3/1000TCbulk SCB/1000TC=bulk CH3/1000TC−bulk CH3end/1000TC and bulk SCB/1000TCis converted to bulk w2 in the same manner as described above.

The LS detector is the 18-angle Wyatt Technology High Temperature DAWNHELEOSII. The LS molecular weight (M) at each point in the chromatogramis determined by analyzing the LS output using the Zimm model for staticlight scattering (Light Scattering from Polymer Solutions; Huglin, M.B., Ed.; Academic Press, 1972):

$\frac{K_{o}c}{\Delta\;{R(\theta)}} = {\frac{1}{{MP}(\theta)} + {2\; A_{2}{c.}}}$

Here, ΔR(θ) is the measured excess Rayleigh scattering intensity atscattering angle θ, c is the polymer concentration determined from theIR5 analysis, A2 is the second virial coefficient, P(θ) is the formfactor for a monodisperse random coil, and K_(o) is the optical constantfor the system:

${K_{o} = \frac{4\pi^{2}{n^{2}\left( {{{dn}/d}\; c} \right)}^{2}}{\lambda^{4}N_{A}}},$where NA is Avogadro's number, and (dn/dc) is the refractive indexincrement for the system. The refractive index, n=1.500 for TCB at 145°C. and λ=665 nm. For analyzing polyethylene homopolymers,ethylene-hexene copolymers, and ethylene-octene copolymers, dn/dc=0.1048ml/mg and A2=0.0015; for analyzing ethylene-butene copolymers,dn/dc=0.1048*(1−0.00126*w2) ml/mg and A2=0.0015 where w2 is weightpercent butene comonomer.

A high temperature Agilent (or Viscotek Corporation) viscometer, whichhas four capillaries arranged in a Wheatstone bridge configuration withtwo pressure transducers, is used to determine specific viscosity. Onetransducer measures the total pressure drop across the detector, and theother, positioned between the two sides of the bridge, measures adifferential pressure. The specific viscosity, ηs, for the solutionflowing through the viscometer is calculated from their outputs. Theintrinsic viscosity, [η], at each point in the chromatogram iscalculated from the equation [η]=ηs/c, where c is concentration and isdetermined from the IR5 broadband channel output. The viscosity MW ateach point is calculated asM=K_(PS)M^(α) ^(PS) ⁺¹/[η], where α_(ps) is 0.67 and K_(ps) is 0.000175.

The branching index (g′vis) is calculated using the output of theGPC-IR5-LS-VIS method as follows. The average intrinsic viscosity,[η]avg, of the sample is calculated by:

${\lbrack\eta\rbrack_{avg} = \frac{\sum{c_{i}\lbrack\eta\rbrack}_{i}}{\sum\; c_{i}}},$where the summations are over the chromatographic slices, i, between theintegration limits. The branching index g′vis is defined as

${g_{vis}^{\prime} = \frac{\lbrack\eta\rbrack_{avg}}{{KM}_{v}^{\alpha}}},$where Mv is the viscosity-average molecular weight based on molecularweights determined by LS analysis and the K and α are for the referencelinear polymer, which are, for purposes of this invention and claimsthereto, α=0.695 and K=0.000579 for linear ethylene polymers, α=0.705and K=0.0002288 for linear propylene polymers, α=0.695 and K=0.000181for linear butene polymers, α is 0.695 and K is0.000579*(1−0.0087*w2b+0.000018*(w2b){circumflex over ( )}2) forethylene-butene copolymer where w2b is a bulk weight percent of butenecomonomer, α is 0.695 and K is 0.000579*(1−0.0075*w2b) forethylene-hexene copolymer where w2b is a bulk weight percent of hexenecomonomer, and α is 0.695 and K is 0.000579*(1−0.0077*w2b) forethylene-octene copolymer where w2b is a bulk weight percent of octenecomonomer. Concentrations are expressed in g/cm³, molecular weight isexpressed in g/mole, and intrinsic viscosity (hence K in theMark-Houwink equation) is expressed in dL/g unless otherwise noted.Calculation of the w2b values is as discussed above.

The reversed-co-monomer index (RCI,m) is computed from ×2 (mol %co-monomer C₃, C₄, C₆, C₈, etc.), as a function of molecular weight,where ×2 is obtained from the following expression in which n is thenumber of carbon atoms in the comonomer (3 for C₃, 4 for C₄, 6 for C₆,etc.):

${x\; 2} = {- {\frac{200\mspace{11mu} w\; 2}{{{- 100}n} - \;{2\mspace{11mu} w\; 2} + {n\; w\; 2}}.}}$

Then the molecular-weight distribution, W(z) where z=log₁₀ M, ismodified to W′(z) by setting to 0 the points in W that are less than 5%of the maximum of W; this is to effectively remove points for which theS/N in the composition signal is low. Also, points of W′ for molecularweights below 2000 gm/mole are set to 0. Then W′ is renormalized so that1=∫_(−∞) ^(∞)W′dz,and a modified weight-average molecular weight (M_(w)′) is calculatedover the effectively reduced range of molecular weights as follows:M_(w)′=∫_(−∞) ^(∞)10^(z)*W′dz.

The RCI,m is then computed asRCI,m=∫ _(−∞) ^(∞)×2(10^(z)−M_(w)′)W′dz.

A reversed-co-monomer index (RCI,w) is also defined on the basis of theweight fraction co-monomer signal (w2/100) and is computed as follows:

${RCI},{w = {\int_{- \infty}^{\infty}{\frac{w\; 2}{100}\left( {10^{z} - M_{w}^{\prime}} \right)W^{\prime}{{dz}.}}}}$

In the above definite integrals the limits of integration are the widestpossible for the sake of generality; however, in reality the function isonly integrated over a finite range for which data is acquired,considering the function in the rest of the non-acquired range to be 0.Also, by the manner in which W′ is obtained, it is possible that W′ is adiscontinuous function, and the above integrations need to be donepiecewise.

Three co-monomer distribution ratios are also defined on the basis ofthe % weight (w2) comonomer signal, denoted as CDR-1,w, CDR-2,w, andCDR-3,w, as follows:

${{CDR} - 1},{w = \frac{w\; 2({Mz})}{w\; 2\left( {M\; w} \right)}},{{CDR} - 2},{w = \frac{w\; 2\left( {M\; z} \right)}{w\; 2\left( \frac{{M\; w} + {M\; n}}{2} \right)}},{{CDR} - 3},{w = \frac{w\; 2\left( \frac{{M\; z} + {M\; w}}{2} \right)}{w\; 2\left( \frac{{M\; w} + {M\; n}}{2} \right)}},$where w2(Mw) is the % weight co-monomer signal corresponding to amolecular weight of Mw, w2(Mz) is the % weight co-monomer signalcorresponding to a molecular weight of Mz, w2[(Mw+Mn)/2)] is the %weight co-monomer signal corresponding to a molecular weight of(Mw+Mn)/2, and w2[(Mz+Mw)/2] is the % weight co-monomer signalcorresponding to a molecular weight of Mz+Mw/2, where Mw is theweight-average molecular weight, Mn is the number-average molecularweight, and Mz is the z-average molecular weight.

Accordingly, the co-monomer distribution ratios can be also definedutilizing the % mole co-monomer signal, CDR-1,m, CDR-2,m, CDR-3,m, as

${{CDR} - 1},{m = \frac{x\; 2({Mz})}{x\; 2\left( {M\; w} \right)}},{{CDR} - 2},{m = \frac{{x2}\left( {M\; z} \right)}{x\; 2\left( \frac{{M\; w} + {M\; n}}{2} \right)}},{{CDR} - 3},{m = \frac{x\; 2\left( \frac{{M\; z} + {M\; w}}{2} \right)}{x\; 2\left( \frac{{M\; w} + {M\; n}}{2} \right)}},$

where x2(Mw) is the % mole co-monomer signal corresponding to amolecular weight of Mw, x2(Mz) is the % mole co-monomer signalcorresponding to a molecular weight of Mz, x2[(Mw+Mn)/2)] is the % moleco-monomer signal corresponding to a molecular weight of (Mw+Mn)/2, andx2[(Mz+Mw)/2] is the % mole co-monomer signal corresponding to amolecular weight of Mz+Mw/2, where Mw is the weight-average molecularweight, Mn is the number-average molecular weight, and Mz is thez-average molecular weight.

Cross-Fractionation Chromatography (CFC)

Cross-fractionation chromatography (CFC) analysis was done using a CFC-2instrument from Polymer Char, S.A., Valencia, Spain. The principles ofCFC analysis and a general description of the particular apparatus usedare given in the article by Ortin, A.; Monrabal, B.; Sancho-Tello, 257J. MACROMOL. SYMP. 13 (2007). A general schematic of the apparatus usedis shown in FIG. 2 of this article. Pertinent details of the analysismethod and features of the apparatus used are as follows.

The solvent used for preparing the sample solution and for elution was1,2-dichlorobenzene (ODCB) which was stabilized by dissolving 2 g of2,6-bis(1,1-dimethylethyl)-4-methylphenol (butylated hydroxytoluene) ina 4-L bottle of fresh solvent at ambient temperature. The sample to beanalyzed (25-125 mg) was dissolved in the solvent (25 ml metered atambient temperature) by stirring (200 rpm) at 150° C. for 75 min. Asmall volume (0.5 ml) of the solution was introduced into a TREF column(stainless steel; o.d., ⅜″; length, 15 cm; packing, non-porous stainlesssteel micro-balls) at 150° C., and the column temperature was stabilizedfor 30 min at a temperature (120-125° C.) approximately 20° C. higherthan the highest-temperature fraction for which the GPC analysis wasincluded in obtaining the final bivariate distribution. The samplevolume was then allowed to crystallize in the column by reducing thetemperature to an appropriate low temperature (30, 0, or −15° C.) at acooling rate of 0.2° C./min. The low temperature was held for 10 minbefore injecting the solvent flow (1 ml/min) into the TREF column toelute the soluble fraction (SF) into the GPC columns (3×PLgel 10 μmMixed-B 300×7.5 mm, Agilent Technologies, Inc.); the GPC oven was heldat high temperature (140° C.). The SF was eluted for 5 min from the TREFcolumn and then the injection valve was put in the “load” position for40 min to completely elute all of the SF through the GPC columns(standard GPC injections). All subsequent higher-temperature fractionswere analyzed using overlapped GPC injections wherein at eachtemperature step the polymer was allowed to dissolve for at least 16 minand then eluted from the TREF column into the GPC column for 3 min. TheIR4 (Polymer Char) infrared detector was used to generate an absorbancesignal that is proportional to the concentration of polymer in theeluting flow.

The universal calibration method was used for determining the molecularweight distribution (MWD) and molecular-weight averages (M_(n), M_(w),etc.) of eluting polymer fractions. Thirteen narrow molecular-weightdistribution polystyrene standards (obtained from Agilent Technologies,Inc.) within the range of 1.5-8200 kg/mol were used to generate auniversal calibration curve. Mark-Houwink parameters were obtained fromAppendix I of Mori, S.; Barth, H. G. Size Exclusion Chromatography;Springer, 1999. For polystyrene K=1.38×10⁻⁴ dl/g and α=0.7; and forpolyethylene K=5.05×10⁻⁴ dl/g and α=0.693 were used. For a polymerfraction, which eluted at a temperature step, that has a weight fraction(weight % recovery) of less than 0.5%, the MWD and the molecular-weightaverages were not computed; additionally, such polymer fractions werenot included in computing the MWD and the molecular-weight averages ofaggregates of fractions.

Additional test methods include the following.

Test Name Method or description Melt Index (I₂), High Load ASTM D-12382.16 kg (MI) or 21.6 kg Melt Index (I₂₁) (HLMI), 190° C. Density ASTMD1505, column density. Samples were molded under ASTM D4703-10a,Procedure C, then conditioned under ASTM D618-08 (23° ± 2° C. and 50 ±10% Relative Humidity) for 40 hours before testingUnless otherwise indicated, room/ambient temperature is approximately23° C.

EXAMPLES

It is to be understood that while the invention has been described inconjunction with the specific embodiments thereof, the foregoingdescription is intended to illustrate and not limit the scope of theinvention. Other aspects, advantages and modifications will be apparentto those skilled in the art to which the invention pertains.

Therefore, the following examples are put forth so as to provide thoseskilled in the art with a complete disclosure and description and arenot intended to limit the scope of that which the inventors regard astheir invention.

Catalyst Preparation

To a stirred reaction vessel was added toluene (2074 lbs) then MAO (1060lbs; 30 wt % Albemarle) followed by a toluene solution of twometallocenes (92 lbs total solution; 12.7 wt % of the hafnocene; 4.2 wt% of the zirconocene). After stirring 60 minutes at 90° F. ES70 silica(PQ Corp) dehydrated at approximately 875° C. (879 lbs) was added to thevessel and stirred for about 1 hour at 90° F. The temperature was raisedto approximately 165° F. the toluene was removed under reduced pressurefor about 20 hours resulting a free flowing powder, yield=1226 lbs. Allsteps were performed under an atmosphere of dry nitrogen. A continuityadditive slurry was co-fed through a separate injection nozzle into thereactor with its own isopentane flush and nitrogen carrier flows, andthe feed rate of continuity agent was adjusted to maintain a totalcontinuity agent concentration between 0-60 ppm by a solids based onreactor bed weight.

Catalyst systems (i.e., mixed/dual catalyst systems) were prepared usinghafnocene (bis(n-propylCp)HfMe₂) and zirconocenes (rac/meso bis(1-Me-Ind)ZrMe₂) and (rac/meso bis (1-Me-Ind)ZrMe₂), where Me=methyl,Eth=ethyl, Ind=indenyl. Dimethyl leaving groups for the metalloceneswere employed although di-chloro versions of the catalyst could havealso been employed.

Upon evaluation and testing to produce LLDPE products, the resultsrevealed high catalyst activity and unique BOCD LLDPE products.

Slurry Preparation

A jacketed mixer is preheated to 60° C. Mineral oil SJCS-380 fromSonnebom is transfer into this vessel. Oil is agitated under<3 psiavacuum at 60 C for 3 hours. The mixer is refilled with N2. Solidcatalyst is transferred into the vessel using N2 pressure. The mixtureis stirred for 2 hours, then cool to 40° C. The well mixed catalystslurry is down-loaded into receiving containers.

Polymerization

Polymerization was conducted in an approximately 600 cubic meter(inclusive of cycle gas volume) gas phase reactor operating at atemperature of about 80° C., a pressure of about 20 barg, with aresidence time of about 2.5 hours. Catalyst was fed into the reactor asa slurry and/or dry powder and monomers were both injected as gases.Steady state was achieved. Ethylene partial pressure was 13.8 bar.Hexene partial pressure was 0.22 bar. Isopentane was used as condensingagent. The polymerization conditions and properties of the polymerproduced in each experimental run is set forth in Table 1.

TABLE 1 Reactor Conditions and Product Properties Sample A B C H₂ conc.(ppm) 410 381 382 Comonomer conc. (mol %) 1.01 1.09 1.06 Ethylene conc.(mol %) 65.8 65.9 65.7 Reactor pressure 290 289 290 Reactor temperature(° F.) 178 181 181 Catalyst slurry feed rate (cc/hr) 35554 36283 44586Catalyst dry feed rate (g/hr) 946 947 0 Trim solution feed rate (g/hr) 08706 2467 Mw (g/mol) 117064 122825 122318 Mn (g/mol) 19653 18725 19440Mz (g/mol) 311480 342231 309710 Mw/Mn 5.96 6.56 6.29 Mz/Mw 2.66 2.792.53 RCI,m (LS) (kg/mol) 179.60 191.90 178.80 CDR2,m 1.96 1.93 1.79T75-T25 (° C.) 23.70 23.80 22.90 Hexene wt % 8.36 8.24 8.37 g′_(vis)0.943 0.931 0.945 Melt Index, MI (dg/min) 1.23 1.12 1.22 High Load MeltIndex, 42.7 42 42.822 HLMI (dg/min) (calc) Melt Index Ratio, MIR 34.737.5 35.1 Gradient density (g/cm³) 0.9212 0.9221 0.9216 Bulk density(g/cm³) 0.4895 0.4661 0.4761

The phrases, unless otherwise specified, “consists essentially of” and“consisting essentially of” do not exclude the presence of other steps,elements, or materials, whether or not, specifically mentioned in thisspecification, so long as such steps, elements, or materials, do notaffect the basic and novel characteristics of the invention,additionally, they do not exclude impurities and variances normallyassociated with the elements and materials used.

For the sake of brevity, only certain ranges are explicitly disclosedherein. However, ranges from any lower limit may be combined with anyupper limit to recite a range not explicitly recited, as well as, rangesfrom any lower limit may be combined with any other lower limit torecite a range not explicitly recited, in the same way, ranges from anyupper limit may be combined with any other upper limit to recite a rangenot explicitly recited. Additionally, within a range includes everypoint or individual value between its end points even though notexplicitly recited. Thus, every point or individual value may serve asits own lower or upper limit combined with any other point or individualvalue or any other lower or upper limit, to recite a range notexplicitly recited.

All priority documents are herein fully incorporated by reference forall jurisdictions in which such incorporation is permitted and to theextent such disclosure is consistent with the description of the presentinvention. Further, all documents and references cited herein, includingtesting procedures, publications, patents, journal articles, etc. areherein fully incorporated by reference for all jurisdictions in whichsuch incorporation is permitted and to the extent such disclosure isconsistent with the description of the present invention.

While the invention has been described with respect to a number ofembodiments and examples, those skilled in the art, having benefit ofthis disclosure, will appreciate that other embodiments can be devisedwhich do not depart from the scope and spirit of the invention asdisclosed herein.

What is claimed is:
 1. A method for producing a polyolefin comprising:a. contacting a first composition and a second composition in a feedline to form a third composition, wherein: i. the first compositioncomprises:
 1. a first bimetallic catalyst, which is a contact product ofi) a hafnocene catalyst, ii) a first zirconocene catalyst, iii) asupport, and iv) an activator, wherein a mol ratio of hafnium tozirconium is from 95:5 to 70:30, and
 2. a diluent, ii. the secondcomposition comprises a second zirconocene catalyst, which is the sameas or different from the first zirconocene catalyst, and a solvent,wherein the second zirconocene catalyst is dissolved in the solvent toform a solution; and iii. the third composition comprises a secondbimetallic catalyst having mol ratio of hafnium to zirconium of from85:15 to 50:50 b. introducing the third composition from the feed lineinto a gas-phase fluidized bed reactor; c. introducing a slurrycomprising continuity agent into the gas-phase fluidized bed reactor; d.introducing feed components into the gas-phase fluidized bed reactor,the feed components comprising hydrogen, ethylene, and a C₃ to C₁₂ alphaolefin comonomer; e. exposing the third composition and the feedcomponents to polymerization conditions comprising: i. a hydrogenconcentration in a range of from 50 ppm to 2000 ppm, ii. an ethyleneconcentration in a range of from 35 mol % to 95 mol %, iii. a comonomerconcentration in a range of from 0.2 mol % to 2 mol %, iv. a reactorpressure in a range of from 200 psig to 500 psig, and v. a reactortemperature in a range of from 100 degrees F. and 250 degrees F., and f.obtaining a polyolefin.
 2. The method of claim 1 wherein the feedcomponents further comprise a third bimetallic catalyst, which is thecontact product of i) a hafnocene catalyst, ii) a zirconocene catalyst,iii) a support, and iv) an activator, wherein a mol ratio of hafnium tozirconium is from 95:5 to 70:30.
 3. The method of claim 2 wherein thethird bimetallic catalyst and the first bimetallic catalyst are thesame.
 4. The method of claim 2 wherein the third bimetallic catalyst andthe first bimetallic catalyst are different.
 5. The method of claim 1wherein the polyolefin is a polyethylene composition comprising at least65 wt % ethylene derived units and from 0.1 to 35 wt % of C₃-C₁₂ olefincomonomer derived units, based upon a total weight of the polyethylenecomposition; wherein the polyethylene composition has: a) a reversedcomonomer index (RCI,m) of 100 kg/mol or greater; and one or more of thefollowing: b) a density of from 0.890 g/cm³ to 0.940 g/cm³; c) a meltindex (MI) of from 0.1 g/10 min to 30 g/10 min; d) a melt index ratio(I₂₁/I₂) of from 10 to 90; e) an M_(w)/M_(n) of from 2 to 16; f) anM_(z)/M_(w) of from 2.5 to 5.0; g) an M_(z)/M_(n) of from 10 to 50; andh) a branching index g′(vis) of 0.90 or greater.
 6. The method of claim1, wherein introducing the continuity agent is carried out such thatconcentration of the continuity agent in the gas-phase fluidized bedreactor is maintained at a concentration between 0 and 60 ppm on thebasis of weight of solids in the gas-phase fluidized bed reactor.
 7. Themethod of claim 1, wherein catalyst productivity of the secondbimetallic catalyst is maintained above 5000 g polyolefin/g supportedcatalyst fed.
 8. The method of claim 1, further comprising optimizing aweight concentration of continuity agent in the bed so as to improvereactor operation while minimizing catalyst impacts on catalystproductivity.
 9. A method for producing a polyolefin comprising: a.introducing a first composition into a gas-phase fluidized bed reactor,wherein the first composition comprises: i. a first bimetallic catalyst,which is a contact product of i) a hafnocene catalyst, ii) a zirconocenecatalyst, iii) a support, and iv) an activator, wherein a mol ratio ofhafnium to zirconium is from 95:5 to 70:30, and ii. a diluent, b.introducing a slurry comprising a continuity agent into the gas-phasefluidized bed reactor; c. introducing feed components into the gas-phasefluidized bed reactor, the feed components comprising hydrogen,ethylene, a C₃ to C₁₂ alpha olefin comonomer, and a second bimetalliccatalyst, which is a contact product of i) a hafnocene catalyst, ii) azirconocene catalyst, iii) a support, and iv) an activator, wherein amol ratio of hafnium to zirconium is from 95:5 to 70:30, d. exposing thefirst composition and the feed components to polymerization conditionscomprising: i. a hydrogen concentration in a range of from 50 ppm to2000 ppm, ii. an ethylene concentration in a range of from 35 mol % to95 mol %, iii. a comonomer concentration in a range of from 0.2 mol % to2 mol %, iv. a reactor pressure in a range of from 200 psig to 500 psig,and v. a reactor temperature in a range of from 100 degrees F. and 250degrees F., and e. obtaining a polyolefin.
 10. The method of claim 9wherein the first bimetallic catalyst and the second bimetallic catalystare the same.
 11. The method of claim 9 wherein the first bimetalliccatalyst and the second bimetallic catalyst are different.
 12. Themethod of claim 9 wherein the polyolefin is a polyethylene compositioncomprising at least 65 wt % ethylene derived units and from 0.1 to 35 wt% of C₃-C₁₂ olefin comonomer derived units, based upon a total weight ofthe polyethylene composition; wherein the polyethylene composition has:a) a reversed comonomer index (RCI,m) of 100 kg/mol or greater, and oneor more of the following: b) a density of from 0.890 g/cm³ to 0.940g/cm³; c) a melt index (MI) of from 0.1 g/10 min to 30 g/10 min; d) amelt index ratio (I₂₁/I₂) of from 10 to 90; e) an M_(w)/M_(n) of from 2to 16; f) an M_(z)/M_(w) of from 2.5 to 5.0; g) an M_(z)/M_(n) of from10 to 50; and h) a branching index g′(vis) of 0.90 or greater.
 13. Themethod of claim 9, wherein introducing the continuity agent is carriedout such that concentration of the continuity agent in the gas-phasefluidized bed reactor is maintained at a concentration between 0 and 60ppm on the basis of weight of solids in the gas-phase fluidized bedreactor.
 14. The method of claim 9, wherein a catalyst productivity ofthe first bimetallic catalyst and the second bimetallic catalyst ismaintained above 5000 g polyolefin/g supported catalyst fed.